Mathematics Question and Solution
Shaded area is;
Area triangle with height = base = √(42) cm - area triangle with height 6.15093874956 cm and base 4.39211425448, and angle 53°
= ½(√(42))² - ½(6.15093874956*4.39211425448)sin53
= 10.212180971 cm²
Area ABCD is;
Area triangle with height 4 cm and base 2√(21) cm + Area triangle with height = base = √(42) cm + area triangle with height √(42) cm and base 10.8160493016 cm.
= ½(4*2√(21))+½(√(42))²+½(√(42)*10.8160493016)
= 74.3783082323 cm²
Area shaded ÷ Area ABCD is;
10.212180971 ÷ 74.3783082323
= 0.13730052772
≈ 0.137
