Question

Translate the words into an appropriate function.
Express the area, A, of a circle as a function of its diameter d.

Answer 1

Area circle = pi * r^2

The diameter of a circle is twice the radius of the circle.

Answer 2

So, r = d/2 where r is the radius and d is the diameter

Answer 3

Area circle = pi * r^2

Area circle = pi * (d/2)^2

@maggielucci What is d/2 times d/2 = ?

Answer 4

The idea is to simplify this: (d/2)^2