Question

find the area of the Pentagon c h i n a if n is equal to 12 cm is equal to 10 cm ACB is equal to 8 cm AC is equal to 7 cm is equal to 7 cm if a is equal to 9 cm and a b is equal to 5 cm.

Shivam mobile yr​

Answer 1

Answer:

Area of pentagon ABCDE= Area of ΔABC+ Area of ΔACD+ Area of ΔADE

Here , BL⊥AC,CM⊥AD,EN⊥AD

So, BL, CM and EN perpendiculars to ΔABC,ΔACD and ΔADE respectively.

Area of triangle with perpendicular =1/2×base×height

∴ Area of ΔABC=1/2×AC×BL

Area of ΔACD=1/2×AD×CM

Area of ΔADE=1/2×AD×EN

Now area of pentagon ABCDE=1/2AC×BL+1/2×AD×CM+1/2×AD×EN

=(1/2×10×3)+(1/2×12×7)+(1/2×12×5)

=15+42+30

=87