Which of the following is the equation of a circle whose center is at the origin and whose diameter has endpoints (-1, 2) and (1, -2)?

x(squared) + y(squared) = 2

x(squared) + y(squared) = 3

x(squared) + y(squared) = 4

x(squared) + y(squared) = 5

Question

Which of the following is the equation of a circle whose center is at the origin and whose diameter has endpoints (-1, 2) and (1, -2)?

x(squared) + y(squared) = 2

x(squared) + y(squared) = 3

x(squared) + y(squared) = 4

x(squared) + y(squared) = 5

anonymous · Answer

@peachpi

anonymous · Answer

Use the distance formula to find the length of the diameter. Then you have to find the radius by dividing the diameter's length by 2.
$$d=\sqrt{(x_2-x_1)^2+(y_2-y_1)^2}$$

anonymous · Answer

I don't understand. Can you help me out a little more? @welshfella

anonymous · Answer

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