Question

Given the equation of a circle below, find the diameter of the circle. Use only the digits 0-9 to enter the diameter.

Answer 1

Answer:

10

Step-by-step explanation:

Standard form for a circle is

(x - h)² + (y - k)² = r²

where (h, k) is the center and r is the radius

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x² + y² - 18x + 24y = -200

Rearrange

(x² - 18x) + (y² + 24y) = -200

Complete the square for x

(x - 9)² + (y² + 24y) = -200 + (-9)²

Complete the sqaure for y

(x - 9)² + (y + 12)² = -200 + (-9)² + 12²

(x - 9)² + (y + 12)² =  25

Now the equation is in standard form

r² = 25

r = 5

Therefor Diameter = 10