If the area of circle p is 1,600 units squared, in units what is the diameter?

area of a circle = PI x r^2

using 3.14 for PI

area = 1600

so 1600 = 3.14 x r^2

r^2 = 1600/3.14 = 509.55

r = square root of 509.55 = 22.57

diameter = r x 2 (22.57 x 2)

diameter = 45.14 units