If a circle has a 16in diameter what is the formula to find its area

The formula is Area = pi * Radius * Radius. Computing the answer gives you 64pi as the area for a circle with a 16in diameter

Step-by-step explanation:

Radius = diameter/2 = 16/2 = 8

Area = pi * radius * radius = pi * 8 * 8 = 64pi

alright so i think for this one it would to draw it out. this may be hard for me to try and draw, but i will do my best on here:

        r

  /       |     \

notice how it forms 2 triangles inside one bigger triangle.

so if we know the angle spr is the same as psr that is saying the measure of angle p is the same as angle s. this means the big triangle psr is either isosceles or equilateral. in both cases, the triangle is perfectly symmetrical when split down the middle, which is in this case rq. because we know it is perfectly symmetrical on both sides, we know that the two triangles inside the bigger one are equal.

how many friends does he have? i think some of the information got cut off in the problem.