It should be the first one since the x and y cross each other out and leave only =-10
A=pie×radius squared is the area formula of a circle. The circumference formula or a circle is C=pie×diameter. 615.75=(3.14)(radius) squared. Divide both sides by the 3.14. What ever 615.75 divided by 3.14 is-is radius squared. The square root is your radius. The radius is half the diameter, so double what you have right now as the radius to get the diameter. Now since C=pie×diameter, your circumference is your pie×your diameter. Whatever your answer is-is your circumference.
Answer:
42
Step-by-step explanation:
First I'm going to assume that C and A are perpendicular.
Because its perpendicular, this creates a 90 degree angle which can be used to create the following equation.

Reduce
11x = 88
x = 8
We then plug in 8 into the equation 6x - 6 in order to solve for that angle.
6(8) - 6
42