10. Construct $ \triangle \mathrm{PQR} $ with $ \mathrm{PQ}=4.5 \mathrm{~cm}, \angle \mathrm{P}=60^{\circ} $ and $ \mathrm{PR}=4.5 \mathrm{~cm} . $ Measure $ \angle \mathrm{Q} $ and $ \angle \mathrm{R} $. What type of a triangle is it?
Given: $PQ=4.5\ cm,\ \angle P=60^{o}$ and $PR=4.5\ cm$.
To do: To construct $\vartriangle PQR$ and and Measure $\angle Q$ and $\angle R$. And to find the type of this triangle.
Solution:
Follow the steps-
1. Draw a line $PQ=4.5\ cm$, with the help of scale.
2. With the help of proctor , Draw $\angle XPQ=60^{o}$.
3. Measure compass to $4.5\ cm$ and mark on $XP$ at point $R$, while $P$ is the center.
4. Join $QR$.
$\vartriangle PQR$, is the required triangle.
With the help of proctor, when we measure $Q$ and $R$. We find it $60^{o}$ both.
And when we measure $QR$, it is $4.5\ cm$.
Here we found that $\angle P=\angle Q=\angle R=60^{o}$ and $PQ=QR=RP=4.5\ cm$.
All its sides and angles are equal.
Hence, It is an equilateral Triangle.
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