I agree with this statement.
A = c/8<span>πb
divide everything other than a from the right side of the equation to get your answer</span>
Given:
.
To find:
The value of r.
Solution:
We have,
.
We know that the radius is perpendicular to the tangent at the point of tangency
AD is the tangent and CD is the radius. So, CD is perpendicular to AD at point D, i.e.,
.
Using Pythagoras theorem, we get




On further simplification, we get



Therefore, the value of r is 9.
The answer is -35 because it says below sea level