Q4, 4y²=60
y=√15 ( i am not sure)
q6, (5+y) ²=81
5+y=9
y=4
q7 (x+4) (x) =77
x²+4x-77=0
(x+11) (x-7) =0
x=-11(rej) or x=7
therefore ,length= 7+4=11cm
breadth=7cm
Answer:
radius 12 units = 452.16 units²
diameter 16.8 units = 221.5584 units²
radius 3.4 units = 36.2984 units²
diameter 10 units = 78.5 units²
Formula for area of circle: 
Answer:
With respect to the reference angle, one leg is the adjacent leg, or the leg right next to the reference angle; and the other leg is the opposite leg, or the leg on the opposite side of the triangle. If two triangles are similar, the ratios of corresponding sides are equal.