Find the equation of the circle with center (-1, 8) and passes through (9, 3). Hint: Use the distance formula.

Answer 1

Get radius r from the distance from the center to the given point.

r = √[(x₁ - x₂)² + (y₁ - y₂)²]

Plug in

x₁ = -1

y₁ = 8

x₂ = 9

y₂ = 3

and get r. Then plug your answer for r and

h = -1

k = 8

into

(x - h)² + (y - k)² = r²

and you are done. Use this same reasoning to answer similar questions that you posted.