Answer:
a) r = 7in
b) d = 30cm
Explanation:
A =
*

A = area of a circle
r = radius
a)A =
*

we divide by
both sides of the equations
=

lets apply square root to both sides of equality sign:

so we have:


r=7 in
b)d= diameter
r=radius
d=2*r


r=15 cm
so we have:
d=2*15cm= 30cm