Found 225 Articles for Class 8

Solve the following equations and verify your answer:
(i) $\frac{7x-2}{5x-1}=\frac{7x+3}{5x+4}$
(ii) $(\frac{x+1}{x+2})^2=\frac{x+2}{x+4}$

Akhileshwar Nani
Updated on 13-Apr-2023 23:45:48

339 Views

Given:The given equations are:(i) $\frac{7x-2}{5x-1}=\frac{7x+3}{5x+4}$(ii) $(\frac{x+1}{x+2})^2=\frac{x+2}{x+4}$To do:We have to solve the given equations and verify the answers.Solution:To verify the answer we have to find the values of the variables and substitute them in the equation. Find the value of LHS and the value of RHS and check whether both are equal.(i) The given equation is $\frac{7x-2}{5x-1}=\frac{7x+3}{5x+4}$$\frac{7x-2}{5x-1}=\frac{7x+3}{5x+4}$On cross multiplication, we get, $(5x+4)(7x-2)=(7x+3)(5x-1)$$5x(7x-2)+4(7x-2)=7x(5x-1)+3(5x-1)$$35x^2-10x+28x-8=35x^2-7x+15x-3$On rearranging, we get, $35x^2-35x^2+18x-8x=-3+8$$10x=5$$x=\frac{5}{10}$$x=\frac{1}{2}$Verification:LHS $=\frac{7x-2}{5x-1}$$=\frac{7(\frac{1}{2})-2}{5(\frac{1}{2})-1}$$=\frac{\frac{7}{2}-2}{\frac{5}{2}-1}$$=\frac{\frac{7-2\times2}{2}}{\frac{5-2\times1}{2}}$$=\frac{\frac{7-4}{2}}{\frac{5-2}{2}}$$=\frac{\frac{3}{2}}{\frac{3}{2}}$$=\frac{3}{2}\times\frac{2}{3}$$=1$RHS $=\frac{7x+3}{5x+4}$$=\frac{7(\frac{1}{2})+3}{5(\frac{1}{2})+4}$$=\frac{\frac{7}{2}+3}{\frac{5}{2}+4}$$=\frac{\frac{7+2\times3}{2}}{\frac{5+2\times4}{2}}$$=\frac{\frac{7+6}{2}}{\frac{5+8}{2}}$$=\frac{\frac{13}{2}}{\frac{13}{2}}$$=\frac{13}{2}\times\frac{2}{13}$$=1$LHS $=$ RHSHence verified.(ii) The given equation is $(\frac{x+1}{x+2})^2=\frac{x+2}{x+4}$$(\frac{x+1}{x+2})^2=\frac{x+2}{x+4}$On cross multiplication, we get, $(x+1)^2(x+4)=(x+2)^2(x+2)$$(x^2+2(x)(1)+1^2)(x+4)=(x^2+2(x)(2)+2^2)(x+2)$$x(x^2+2x+1)+4(x^2+2x+1)=x(x^2+4x+4)+2(x^2+4x+4)$$x^3+2x^2+x+4x^2+8x+4=x^3+4x^2+4x+2x^2+8x+8$On rearranging, we get, $x^3-x^3+6x^2-6x^2+9x-12x=8-4$$-3x=4$$x=\frac{-4}{3}$Verification:LHS $=(\frac{x+1}{x+2})^2$$=(\frac{\frac{-4}{3}+1}{\frac{-4}{3}+2})^2$$=(\frac{\frac{-4+3\times1}{3}}{\frac{-4+2\times3}{3}})^2$$=(\frac{\frac{-4+3}{3}}{\frac{-4+6}{3}})^2$$=(\frac{\frac{-1}{3}}{\frac{2}{3}})^2$$=(\frac{-1}{3})^2\times(\frac{3}{2})^2$$=\frac{1}{9}\times\frac{9}{4}$$=\frac{1}{4}$RHS $=\frac{x+2}{x+4}$$=\frac{\frac{-4}{3}+2}{\frac{-4}{3}+4}$$=\frac{\frac{-4+2\times3}{3}}{\frac{-4+4\times3}{3}}$$=\frac{\frac{-4+6}{3}}{\frac{-4+12}{3}}$$=\frac{\frac{2}{3}}{\frac{8}{3}}$$=\frac{2}{3}\times\frac{3}{8}$$=\frac{1}{1}\times\frac{1}{4}$$=\frac{1}{4}$LHS $=$ RHSHence verified.Read More

Solve the following equations and verify your answer:
(i) $\frac{2}{3x}-\frac{3}{2x}=\frac{1}{12}$
(ii) $\frac{3x+5}{4x+2}=\frac{3x+4}{4x+7}$

Akhileshwar Nani
Updated on 13-Apr-2023 23:24:36

188 Views

Given:The given equations are:(i) $\frac{2}{3x}-\frac{3}{2x}=\frac{1}{12}$(ii) $\frac{3x+5}{4x+2}=\frac{3x+4}{4x+7}$To do:We have to solve the given equations and verify the answers.Solution:To verify the answer we have to find the values of the variables and substitute them in the equation. Find the value of LHS and the value of RHS and check whether both are equal.(i) The given equation is $\frac{2}{3x}-\frac{3}{2x}=\frac{1}{12}$$\frac{2}{3x}-\frac{3}{2x}=\frac{1}{12}$LCM of denominators $3x$ and $2x$ is $6x$$\frac{2(2)-3(3)}{6x}=\frac{1}{12}$$\frac{4-9}{6x}=\frac{1}{12}$$\frac{-5}{6x}=\frac{1}{12}$On cross multiplication, we get, $12(-5)=(1)(6x)$$-60=6x$$6x=-60$$x=\frac{-60}{6}$$x=-10$Verification:LHS $=\frac{2}{3x}-\frac{3}{2x}$$=\frac{2}{3(-10)}-\frac{3}{2(-10)}$$=\frac{2}{-30}-\frac{3}{-20}$$=\frac{-1}{15}+\frac{3}{20}$$=\frac{-1\times4+3\times3}{60}$                  (LCM of $15$ and $20$ is $60$)$=\frac{-4+9}{60}$$=\frac{5}{60}$$=\frac{1}{12}$RHS $=\frac{1}{12}$LHS $=$ RHSHence verified.(ii) The given equation is $\frac{3x+5}{4x+2}=\frac{3x+4}{4x+7}$$\frac{3x+5}{4x+2}=\frac{3x+4}{4x+7}$On cross multiplication, we get, $(3x+5)(4x+7)=(3x+4)(4x+2)$$3x(4x+7)+5(4x+7)=3x(4x+2)+4(4x+2)$$12x^2+21x+20x+35=12x^2+6x+16x+8$On rearranging, we get, $12x^2-12x^2+41x-22x=8-35$$19x=-27$$x=\frac{-27}{19}$Verification:LHS $=\frac{3x+5}{4x+2}$$=\frac{3(\frac{-27}{19})+5}{4(\frac{-27}{19})+2}$$=\frac{\frac{3\times(-27)}{19}+5}{\frac{4\times(-27)}{19}+2}$$=\frac{\frac{-81+5\times19}{19}}{\frac{-108+2\times19}{19}}$$=\frac{\frac{-81+95}{19}}{\frac{-108+38}{19}}$$=\frac{\frac{14}{19}}{\frac{-70}{19}}$$=\frac{14}{19}\times\frac{19}{-70}$$=\frac{1}{1}\times\frac{1}{-5}$$=\frac{-1}{5}$RHS $=\frac{3x+4}{4x+7}$$=\frac{3(\frac{-27}{19})+4}{4(\frac{-27}{19})+7}$$=\frac{\frac{3\times(-27)}{19})+4}{\frac{4\times(-27)}{19})+7}$$=\frac{\frac{-81+19\times4}{19}}{\frac{-108+19\times7}{19}}$$=\frac{\frac{-81+76}{19}}{\frac{-108+133}{19}}$$=\frac{\frac{-5}{19}}{\frac{25}{19}}$$=\frac{-5}{19}\times\frac{19}{25}$$=\frac{-1}{1}\times{1}{5}$$=\frac{-1}{5}$LHS ... Read More

Solve the following equations and verify your answer:
(i) $\frac{y-(7-8y)}{9y-(3+4y)}=\frac{2}{3}$
(ii) $\frac{6}{2x-(3-4x)}=\frac{2}{3}$

Akhileshwar Nani
Updated on 13-Apr-2023 23:23:54

173 Views

Given:The given equations are:(i) $\frac{y-(7-8y)}{9y-(3+4y)}=\frac{2}{3}$(ii) $\frac{6}{2x-(3-4x)}=\frac{2}{3}$To do:We have to solve the given equations and verify the answers.Solution:To verify the answer we have to find the values of the variables and substitute them in the equation. Find the value of LHS and the value of RHS and check whether both are equal.(i) The given equation is $\frac{y-(7-8y)}{9y-(3+4y)}=\frac{2}{3}$$\frac{y-7+8y}{9y-3-4y}=\frac{2}{3}$$\frac{9y-7}{5y-3}=\frac{2}{3}$On cross multiplication, we get, $3(9y-7)=(2)(5y-3)$$3(9y)-3(7)=2(5y)-2(3)$$27y-21=10y-6$On rearranging, we get, $27y-10y=-6+21$$17y=15$$y=\frac{15}{17}$Verification:LHS $=\frac{y-(7-8y)}{9y-(3+4y)}$$=\frac{\frac{15}{17}-(7-8(\frac{15}{17}))}{9(\frac{15}{17})-(3+4(\frac{15}{17}))}$$=\frac{\frac{15}{17}-(7-(\frac{-8\times15}{17}))}{\frac{9\times15}{17}-(3+\frac{4\times15}{17})}$$=\frac{\frac{15}{17}-(7-(\frac{120}{17}))}{\frac{135}{17}-(3+\frac{60}{17})}$$=\frac{\frac{15}{17}-(\frac{7\times17-120}{17})}{\frac{135}{17}-(\frac{3\times17+60}{17})}$$=\frac{\frac{15}{17}-(\frac{119-120}{17})}{\frac{135}{17}-(\frac{51+60}{17})}$$=\frac{\frac{15}{17}-(\frac{-1}{17})}{\frac{135}{17}-(\frac{111}{17})}$$=\frac{\frac{15+1}{17}}{\frac{135-111}{17}}$$=\frac{\frac{16}{17}}{\frac{24}{17}}$$=\frac{16}{17}\times\frac{17}{24}$$=\frac{2}{3}$RHS $=\frac{2}{3}$LHS $=$ RHSHence verified.(ii) The given equation is $\frac{6}{2x-(3-4x)}=\frac{2}{3}$$\frac{6}{2x-(3-4x)}=\frac{2}{3}$$\frac{6}{2x-3+4x}=\frac{2}{3}$$\frac{6}{6x-3}=\frac{2}{3}$On cross multiplication, we get, $3(6)=2(6x-3)$$18=2(6x)-2(3)$$18=12x-6$On rearranging, we get, $12x=18+6$$12x=24$$x=\frac{24}{12}$$x=2$Verification:LHS $=\frac{6}{2x-(3-4x)}$$=\frac{6}{2(2)-(3-4(2))}$$=\frac{6}{4-(3-8)}$$=\frac{6}{4+5}$$=\frac{6}{9}$$=\frac{2}{3}$RHS $=\frac{2}{3}$LHS $=$ RHSHence verified.Read More

Solve the following equations and verify your answer:
(i) $\frac{1-9y}{19-3y}=\frac{5}{8}$
(ii) $\frac{2x}{3x+1}=1$

Akhileshwar Nani
Updated on 13-Apr-2023 23:23:17

143 Views

Given:The given equations are:(i) $\frac{1-9y}{19-3y}=\frac{5}{8}$(ii) $\frac{2x}{3x+1}=1$To do:We have to solve the given equations and verify the answers.Solution:To verify the answer we have to find the values of the variables and substitute them in the equation. Find the value of LHS and the value of RHS and check whether both are equal.(i) The given equation is $\frac{1-9y}{19-3y}=\frac{5}{8}$$\frac{1-9y}{19-3y}=\frac{5}{8}$On cross multiplication, we get, $8(1-9y)=(5)(19-3y)$$8(1)-8(9y)=5(19)-5(3y)$$8-72y=95-15y$On rearranging, we get, $72y-15y=8-95$$57y=-87$$y=\frac{-87}{57}$$y=\frac{-29}{19}$Verification:LHS $=\frac{1-9y}{19-3y}$$=\frac{1-9(\frac{-29}{19})}{19-3(\frac{-29}{19})}$$=\frac{1+\frac{29\times9}{19}}{19+\frac{3\times29}{19}}$$=\frac{1+\frac{261}{19}}{19+\frac{87}{19}}$$=\frac{\frac{19\times1+261}{19}}{\frac{19\times19+87}{19}}$$=\frac{\frac{19+261}{19}}{\frac{361+87}{19}}$$=\frac{\frac{280}{19}}{\frac{448}{19}}$$=\frac{280}{19}\times\frac{19}{448}$$=\frac{280}{448}$$=\frac{5}{8}$RHS $=\frac{5}{8}$LHS $=$ RHSHence verified.(ii) The given equation is $\frac{2x}{3x+1}=1$$\frac{2x}{3x+1}=1$On cross multiplication, we get, $2x=1(3x+1)$$2x=3x+1$On rearranging, we get, $3x-2x=-1$$x=-1$Verification:LHS $=\frac{2x}{3x+1}$$=\frac{2(-1)}{3(-1)+1}$$=\frac{-2}{-3+1}$$=\frac{-2}{-2}$$=1$RHS $=1$LHS $=$ RHSHence verified.Read More

Solve the following equations and verify your answer:
(i) $\frac{2y+5}{y+4}=1$
(ii) $\frac{2x+1}{3x-2}=\frac{5}{9}$

Akhileshwar Nani
Updated on 13-Apr-2023 23:22:39

107 Views

Given:The given equations are:(i) $\frac{2y+5}{y+4}=1$(ii) $\frac{2x+1}{3x-2}=\frac{5}{9}$To do:We have to solve the given equations and verify the answers.Solution:To verify the answer we have to find the values of the variables and substitute them in the equation. Find the value of LHS and the value of RHS and check whether both are equal.(i) The given equation is $\frac{2y+5}{y+4}=1$$\frac{2y+5}{y+4}=1$On cross multiplication, we get, $2y+5=(1)(y+4)$$2y+5=y+4$On rearranging, we get, $2y-y=4-5$$y=-1$Verification:LHS $=\frac{2y+5}{y+4}$$=\frac{2(-1)+5}{(-1)+4}$$=\frac{-2+5}{-1+4}$$=\frac{3}{3}$$=1$RHS $=1$LHS $=$ RHSHence verified.(ii) The given equation is $\frac{2x+1}{3x-2}=\frac{5}{9}$$\frac{2x+1}{3x-2}=\frac{5}{9}$On cross multiplication, we get, $9(2x+1)=5(3x-2)$$9(2x)+9(1)=5(3x)-5(2)$$18x+9=15x-10$On rearranging, we get, $18x-15x=-10-9$$3x=-19$$x=\frac{-19}{3}$Verification:LHS $=\frac{2x+1}{3x-2}$$=\frac{2(\frac{-19}{3})+1}{3(\frac{-19}{3})-2}$$=\frac{\frac{2\times(-19)}{3}+1}{-19-2}$$=\frac{\frac{-38+1\times3}{3}}{-21}$$=\frac{\frac{-38+3}{3}}{-21}$$=\frac{\frac{-35}{3}}{-21}$$=\frac{-35}{3\times-21}$$=\frac{5}{3\times3}$$=\frac{5}{9}$RHS $=\frac{5}{9}$LHS $=$ RHSHence verified.Read More

Solve the following equations and verify your answer:
(i) $\frac{5x-7}{3x}=2$
(ii) $\frac{3x+5}{2x+7}=4$

Akhileshwar Nani
Updated on 13-Apr-2023 23:21:21

201 Views

Given:The given equations are:(i) $\frac{5x-7}{3x}=2$(ii) $\frac{3x+5}{2x+7}=4$To do:We have to solve the given equations and verify the answers.Solution:To verify the answer we have to find the values of the variables and substitute them in the equation. Find the value of LHS and the value of RHS and check whether both are equal.(i) The given equation is $\frac{5x-7}{3x}=2$$\frac{5x-7}{3x}=2$On cross multiplication, we get, $5x-7=3x(2)$$5x-7=6x$On rearranging, we get, $6x-5x=-7$$x=-7$Verification:LHS $=\frac{5x-7}{3x}$$=\frac{5(-7)-7}{3(-7)}$$=\frac{-35-7}{-21}$$=\frac{-42}{-21}$$=2$RHS $=2$LHS $=$ RHSHence verified.(ii) The given equation is $\frac{3x+5}{2x+7}=4$.$\frac{3x+5}{2x+7}=4$On cross multiplication, we get, $3x+5=4(2x+7)$$3x+5=4(2x)+4(7)$$3x+5=8x+28$On rearranging, we get, $8x-3x=5-28$$5x=-23$$x=\frac{-23}{5}$Verification:LHS $=\frac{3x+5}{2x+7}$$=\frac{3(\frac{-23}{5})+5}{2(\frac{-23}{5})+7}$$=\frac{\frac{-69}{5}+5}{\frac{-46}{5}+7}$$=\frac{\frac{-69+5\times5}{5}}{\frac{-46+5\times7}{5}}$$=\frac{\frac{-69+25}{5}}{\frac{-46+35}{5}}$$=\frac{\frac{-44}{5}}{\frac{-11}{5}}$$=\frac{-44}{5}\times\frac{5}{-11}$$=\frac{4}{1}\times\frac{1}{1}$$=4$RHS $=4$LHS $=$ RHSHence verified.Read More

Solve the following equations and verify your answer:
(i) $\frac{2x-3}{3x+2}=\frac{-2}{3}$
(ii) $\frac{2-y}{y+7}=\frac{3}{5}$

Akhileshwar Nani
Updated on 13-Apr-2023 23:20:50

124 Views

Given:The given equations are:(i) $\frac{2x-3}{3x+2}=\frac{-2}{3}$(ii) $\frac{2-y}{y+7}=\frac{3}{5}$To do:We have to solve the given equations and verify the answers.Solution:To verify the answer we have to find the values of the variables and substitute them in the equation. Find the value of LHS and the value of RHS and check whether both are equal.(i) The given equation is $\frac{2x-3}{3x+2}=\frac{-2}{3}$$\frac{2x-3}{3x+2}=\frac{-2}{3}$On cross multiplication, we get, $3(2x-3)=(-2)(3x+2)$$3(2x)-3(3)=-2(3x)-2(2)$$6x-9=-6x-4$On rearranging, we get, $6x+6x=9-4$$12x=5$$x=\frac{5}{12}$Verification:LHS $=\frac{2x-3}{3x+2}$$=\frac{2(\frac{5}{12})-3}{3(\frac{5}{12}+2}$$=\frac{\frac{5}{6}-3}{\frac{5}{4}+2}$$=\frac{\frac{5-3\times6}{6}}{\frac{5+2\times4}{4}}$$=\frac{5-18}{6}\times\frac{4}{5+8}$$=\frac{-13}{6}\times\frac{4}{13}$$=\frac{-1}{3}\times\frac{2}{1}$$=\frac{-2}{3}$RHS $=\frac{-2}{3}$LHS $=$ RHSHence verified.(ii) The given equation is $\frac{2-y}{y+7}=\frac{3}{5}$.$\frac{2-y}{y+7}=\frac{3}{5}$On cross multiplication, we get, $5(2-y)=3(y+7)$$5(2)-5(y)=3(y)+3(7)$$10-5y=3y+21$On rearranging, we get, $5y+3y=10-21$$8y=-11$$y=\frac{-11}{8}$Verification:LHS $=\frac{2-y}{y+7}$$=\frac{2-(\frac{-11}{8})}{\frac{-11}{8}+7}$$=\frac{2+\frac{11}{8}}{\frac{-11}{8}+7}$$=\frac{\frac{2\times8+11}{8}}{\frac{-11+7\times8}{8}}$$=\frac{\frac{16+11}{8}}{\frac{-11+56}{8}}$$=\frac{\frac{27}{8}}{\frac{45}{8}}$$=\frac{27}{8}\times\frac{8}{45}$$=\frac{3}{1}\times\frac{1}{5}$$=\frac{3}{5}$RHS $=\frac{3}{5}$LHS $=$ RHSHence verified.Read More

Solve the following equation and also check your result:
$[(2x+3)+(x+5)]^2+[(2x+3)-(x+5)]^2=10x^2 + 92$

Akhileshwar Nani
Updated on 13-Apr-2023 23:20:07

190 Views

Given:The given equation is $[(2x+3)+(x+5)]^2+[(2x+3)-(x+5)]^2=10x^2 + 92$To do:We have to solve the given equation and check the result.Solution:To check the result we have to find the values of the variables and substitute them in the equation. Find the value of LHS and the value of RHS and check whether both are equal.The given equation is $[(2x+3)+(x+5)]^2+[(2x+3)-(x+5)]^2=10x^2 + 92$$[(2x+3)+(x+5)]^2+[(2x+3)-(x+5)]^2=10x^2 + 92$$[3x+8]^2+[x-2]^2=10x^2 + 92$$(3x)^2+2(3x)(8)+8^2+x^2-2(x)(2)+2^2=10x^2+92$             [Since $(a+b)^2=a^2+2ab+b^2$ and $(a-b)^2=a^2-2ab+b^2$]$9x^2+48x+64+x^2-4x+4=10x^2+92$$10x^2+44x+68=10x^2+92$On rearranging, we get, $10x^2-10x^2+44x=92-68$$44x=24$$x=\frac{24}{44}$$x=\frac{6}{11}$Verification:LHS $=[(2x+3)+(x+5)]^2+[(2x+3)-(x+5)]^2$$=[(2(\frac{6}{11})+3)+(\frac{6}{11}+5)]^2+[(2(\frac{6}{11})+3)-(\frac{6}{11}+5)]^2$$=[\frac{12}{11}+3)+(\frac{6}{11}+5)]^2+[(\frac{12}{11})+3)-(\frac{6}{11}+5)]^2$$=[\frac{12+6}{11}+8]^2+[\frac{12-6}{11}-2]^2$$=[\frac{18}{11}+8]^2+[\frac{6}{11}-2]^2$$=[\frac{18+11\times8}{11}]^2+[\frac{6-2\times11}{11}]^2$$=[\frac{18+88}{11}]^2+[\frac{6-22}{11}]^2$$=[\frac{106}{11}]^2+[\frac{-16}{11}]^2$$=\frac{11236}{121}+\frac{256}{121}$$=\frac{11236+256}{121}$$=\frac{11492}{121}$RHS $=10x^2 + 92$$=10(\frac{6}{11})^2 + 92$$=10(\frac{36}{121})+92$$=\frac{360}{121}+92$$=\frac{360+121\times92}{121}$$=\frac{360+11132}{121}$$=\frac{11492}{121}$LHS $=$ RHSHence verified.Read More

Solve each of the following equations and also check your results in each case:
(i) $6.5x+(\frac{19.5x-32.5}{2})=6.5x+13+\frac{13x-26}{2}$
(ii) $(3x-8)(3x+2)-(4x-11)(2x+1)=(x-3)(x+7)$

Akhileshwar Nani
Updated on 13-Apr-2023 23:18:51

116 Views

Given:The given equations are:(i) $6.5x+(\frac{19.5x-32.5}{2})=6.5x+13+\frac{13x-26}{2}$(ii) $(3x-8)(3x+2)-(4x-11)(2x+1)=(x-3)(x+7)$To do:We have to solve the given equations and check the results.Solution:To check the results we have to find the values of the variables and substitute them in the equation. Find the value of LHS and the value of RHS and check whether both are equal.(i) The given equation is $6.5x+(\frac{19.5x-32.5}{2})=6.5x+13+\frac{13x-26}{2}$$6.5x+(\frac{19.5x-32.5}{2})=6.5x+13+\frac{13x-26}{2}$On rearranging, we get, $6.5x+(\frac{19.5x-32.5}{2})-6.5x-\frac{13x-26}{2}=13$$\frac{19.5x-32.5}{2}-\frac{13x-26}{2}=13$$\frac{19.5x-32.5-(13x-26)}{2}=13$$\frac{19.5x-32.5-13x+26}{2}=13$$\frac{6.5x-6.5}{2}=13$On cross multiplication, we get, $6.5x-6.5=13\times2$$6.5x-6.5=26$$6.5x=26+6.5$$6.5x=32.5$$x=\frac{32.5}{6.5}$$x=5$Verification:LHS $=6.5x+(\frac{19.5x-32.5}{2})$$=6.5(5)+(\frac{19.5(5)-32.5}{2})$$=32.5+\frac{97.5-32.5}{2}$$=32.5+\frac{65}{2}$$=32.5+32.5$$=65$RHS $=6.5x+13+\frac{13x-26}{2}$$=6.5(5)+13+\frac{13(5)-26}{2}$$=32.5+13+\frac{65-26}{2}$$=32.5+13+\frac{39}{2}$$=45.5+19.5$$=65$LHS $=$ RHSHence verified.(ii) The given equation is $(3x-8)(3x+2)-(4x-11)(2x+1)=(x-3)(x+7)$.$(3x-8)(3x+2)-(4x-11)(2x+1)=(x-3)(x+7)$$3x(3x+2)-8(3x+2)-4x(2x+1)+11(2x+1)=x(x+7)-3(x+7)$$9x^2+6x-24x-16-8x^2-4x+22x+11=x^2+7x-3x-21$$x^2-5=x^2+4x-21$$x^2-x^2+4x=21-5$$4x=16$$x=\frac{16}{4}$$x=4$Verification:LHS $=(3x-8)(3x+2)-(4x-11)(2x+1)$$=[3(4)-8][3(4)+2]-[4(4)-11][2(4)+1]$$=(12-8)(12+2)-(16-11)(8+1)$$=4(14)-5(9)$$=56-45$$=11$RHS $=(x-3)(x+7)$$=(4-3)(4+7)$$=1(11)$$=11$LHS $=$ RHSHence verified.Read More

Solve each of the following equations and also check your results in each case:
(i) $\frac{7x-1}{4}-\frac{1}{3}(2x-\frac{1-x}{2})=\frac{10}{3}$
(ii) $0.5\frac{(x-0.4)}{0.35}-0.6(\frac{x-2.71}{0.42})=x+6.1$

Akhileshwar Nani
Updated on 13-Apr-2023 23:17:26

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Given:The given equations are:(i) $\frac{7x-1}{4}-\frac{1}{3}(2x-\frac{1-x}{2})=\frac{10}{3}$(ii) $0.5\frac{(x-0.4)}{0.35}-0.6(\frac{x-2.71}{0.42})=x+6.1$To do:We have to solve the given equations and check the results.Solution:To check the results we have to find the values of the variables and substitute them in the equation. Find the value of LHS and the value of RHS and check whether both are equal.(i) The given equation is $\frac{7x-1}{4}-\frac{1}{3}(2x-\frac{1-x}{2})=\frac{10}{3}$$\frac{7x-1}{4}-\frac{1}{3}(2x-\frac{1-x}{2})=\frac{10}{3}$$\frac{7x-1}{4}-\frac{1}{3}(\frac{2(2x)-(1-x)}{2})=\frac{10}{3}$$\frac{7x-1}{4}-\frac{1}{3}(\frac{4x-1+x}{2})=\frac{10}{3}$$\frac{7x-1}{4}-(\frac{5x-1}{2\times3})=\frac{10}{3}$$\frac{7x-1}{4}-\frac{5x-1}{6}=\frac{10}{3}$LCM of denominators $4$ and $6$ is $12$$\frac{(7x-1)\times3-(5x-1)\times2}{12}=\frac{10}{3}$$\frac{3(7x)-3(1)-2(5x)+2(1)}{12}=\frac{10}{3}$$\frac{21x-3-10x+2}{12}=\frac{10}{3}$$\frac{11x-1}{12}=\frac{10}{3}$On cross multiplication, we get, $11x-1=\frac{10\times12}{3}$$11x-1=10\times4$$11x-1=40$$11x=40+1$$11x=41$$x=\frac{41}{11}$Verification:LHS $=\frac{7x-1}{4}-\frac{1}{3}(2x-\frac{1-x}{2})$$=\frac{7(\frac{41}{11})-1}{4}-\frac{1}{3}(2(\frac{41}{11})-\frac{1-(\frac{41}{11})}{2})$$=\frac{\frac{41\times7}{11}-1}{4}-\frac{1}{3}(\frac{41\times2}{11}-\frac{\frac{11\times1-41}{11}}{2})$$=\frac{\frac{287}{11}-1}{4}-\frac{1}{3}(\frac{82}{11}-\frac{\frac{11-41}{11}}{2})$$=\frac{287-11}{11\times4}-\frac{1}{3}(\frac{82}{11}-\frac{-30}{11\times2})$$=\frac{276}{44}-\frac{1}{3}(\frac{82}{11}+\frac{30}{22})$$=\frac{69}{11}-\frac{1}{3}(\frac{82\times2+30}{22})$$=\frac{69}{11}-\frac{1}{3}(\frac{164+30}{22})$$=\frac{69}{11}-\frac{1}{3}(\frac{194}{22})$$=\frac{69}{11}-(\frac{194}{3\times22})$$=\frac{69}{11}-\frac{194}{66}$$=\frac{69\times6-194}{66}$$=\frac{414-194}{66}$$=\frac{220}{66}$$=\frac{10}{3}$RHS $=\frac{10}{3}$LHS $=$ RHSHence verified.(ii) The given equation is $0.5\frac{(x-0.4)}{0.35}-0.6(\frac{x-2.71}{0.42})=x+6.1$$0.5\frac{(x-0.4)}{0.35}-0.6(\frac{x-2.71}{0.42})=x+6.1$On rearranging, we get, $0.5\frac{(x-0.4)}{0.35}-0.6(\frac{x-2.71}{0.42})-x=6.1$$\frac{(x-0.4)}{0.7}-(\frac{x-2.71}{0.7})-x=6.1$$\frac{x-0.4-(x-2.71)}{0.7}-x=6.1$$\frac{x-0.4-x+2.71}{0.7}-x=6.1$$\frac{2.31}{0.7}-x=6.1$$\frac{23.1}{7}-6.1=x$$x=3.3-6.1$$x=-2.8$Verification:LHS $=0.5\frac{(x-0.4)}{0.35}-0.6(\frac{x-2.71}{0.42})$$=0.5\frac{(-2.8-0.4)}{0.35}-0.6(\frac{-2.8-2.71}{0.42})$$=\frac{-3.2}{0.7}-\frac{-5.51}{0.7}$$=\frac{-3.2+5.51}{0.7}$$=\frac{2.31}{0.7}$$=3.3$RHS $=x+6.1$$=-2.8+6.1$$=3.3$LHS $=$ RHSHence verified.Read More

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