If a circle has center (a,b) and radius r, the equation is

So, you have

Answer:
-6
Step-by-step explanation:
(y2-y1) / (x2-x1)
(-16-(-10)) / (2-1)
(-6) / (1)
= -6
Take any two points in the graph and put them into the formula.
2pi/3 has the same Sin, Cos, & Tan as pi/3 in QI except for the SIGNS.
2pi/3 is in QII so Cos is negative and Tangent is negative, Sine is still positive.
Sin 2pi/3 = √(3) / 2
Cos 2pi/3 = -1/2
Tan 2pi/3 = -√3
6*40=240. 4*40=160. 240*160=38400. 38400 is your answer.