Mathematics Question and Solution
a = 10+10
a = 20 cm.
a is twice the radius of the quarter circle.
b = ½(10)
b = 5 cm.
c² = 5²+10²
c √(125)
c = 5√(5) cm.
Observing similar plane shape (right-angled triangle) side length ratios.
20 - 5√(5)
d - 5
Cross Multiply.
5√(5)d = 100
d = 20/√(5)
d = 4√(5) cm.
e² = 20²-(4√(5))²
e² = 400-80
e = √(320)
e = 8√(5) cm.
f = e-c
f = 8√(5)-5√(5)
f = 3√(5) cm.
Therefore, area blue is;
Area triangle with height 4√(5) cm and base 3√(5) cm + Area triangle with height 10 cm and base 5 cm.
= ½*4√(5)*3√(5)+½*10*5
= ½(60+50)
= ½(110)
= 55 cm²
