Question

Write the equation of the circle given center: (1,-3) and diameter:20

I put it as (x-1)^2+(y+3)^2=400

Answer 1

(x - 1)^2 + (y + 3)^2 = 400.

Explanation:

Your equation is correct.

The center of the circle is (1, -3), which is the midpoint of the diameter. The diameter is 20, so the radius is 10. The equation of a circle with center (h, k) and radius r is given by:

(x - h)^2 + (y - k)^2 = r^2

Substituting the values, we get:

(x - 1)^2 + (y + 3)^2 = 10^2

Simplifying the right side, we get:

(x - 1)^2 + (y + 3)^2 = 100

Therefore, the equation of the circle is (x - 1)^2 + (y + 3)^2 = 400.