## anonymous one year ago 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

1. anonymous

@peachpi

2. anonymous

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. $d=\sqrt{(x_2-x_1)^2+(y_2-y_1)^2}$

3. anonymous

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

4. anonymous

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5. anonymous

@cheyennerae1605