The area of trapezium ABCD in the given figure is
Given:
∠BEC = 90°
∠DAE = 90°
CD = AE = 8cm
BE = 15cm
BC = 17cm
Consider ΔCEB
Here, By Pythagoras theorem
BC2 = CE2 + EB2
172 = CE2 + 152
CE2 = 172 – 152
CE2 = 289 – 225 = 64
CE = 8
Here,
∠AEC = 90°
CD = CE = 8cm
∴ AECD is a Square.
∴ Area (Trap. ABCD) = Area (Sq. AECD) + Area (ΔCEB)
Area (Trap. ABCD) = AE×EC + 1/2×CE×EB
Area (Trap. ABCD) = 8×8 + 1/2×8×15 = 64 + 60 = 104cm2
∴ Area (Trap. ABCD) = 124cm2