Question

What is the center of the circle?

The circle passes through the pint (-2,3). What is it’s radius?

Answer 1

Explanation:

Use the formula for circles.

`x^(2) + y^(2) = r^(2)`

Since we already have the values of x and y in the given problem (-2,3), substitute the values in the fomula.

`x^(2) + y^(2) = r^(2)`

`(-2)^(2) + (3)^(2) = r^(2)`

`4 + 9 = r^(2)`

`13 = r^(2)` (square both sides to get the radius)

`√(13) = \sqrt{r^(2) }`

`√(13) = r`