In parallelogram ABCD, angle $a = 2x + 25$ and angle $b= 3x -5$ so find all the angles.
Given: In parallelogram ABCD, angle $a = 2x + 25$ and angle $b= 3x -5$.
To do: Find all angles
Answer:
In a parallelogram, adjacent angles are supplementary.
Angle A and angle B are adjacent angles and hence are supplementary.
$A + B = 2x + 25 + 3x -5 = 180°$
$5x + 20 = 180; 5x = 180 - 20 = 160$
$x = \frac{160}{5} = 32°$.
So angle $A = 2x + 25 = 2(32) + 25 = 64 + 25 = 89°$
So angle $B = 3x - 5 = 3(32) - 5 = 96 - 5 = 91°$
So $A = 89°$ and $B = 91°$
Since opposite angles of a parallelogram are equal
∠A = ∠C = 89° and ∠B = ∠D = 91°
So the angles the parallelogram are ∠A =89°; ∠B = 91°, ∠C = 89°; ∠D = 91°
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