In an isosceles triangle, the unequal side is $22 cm$ and perimeter is $144 cm.$ Find its area.

 In the figure given alongside, $PQR$ is an equilateral triangle of side $20 cm$. $∆QSR$ is inscribed in it, angle $QSR = 90°, QS = 16cm$. Find $SR$.

 In the figure given alongside, $PQR$ is an equilateral triangle of side $20 cm$. $∆QSR$ is inscribed in it, angle $QSR = 90°, QS = 16cm$. Find  the area of the shaded portion.

 In $∆ABC, AB = 15cm, AC = 20cm$ and $\angle BAC = 90°$. Find the area of $∆ABC$

 In $∆ABC, AB = 15cm, AC = 20cm$ and $\angle BAC = 90°$. Find the length of $AD$ if $AD\perp BC$.

 In $∆ABC, AB = 15cm, AC = 20cm$ and $\angle BAC = 90°$. Find the area of $△ABD$

. In triangle $PQR$, $\angle Q=\angle R = 45°$ and $QR = 10cm$. Find its area.