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A diameter of a circle has endpoints A (-6, -8) and B (2, 10).
Find the center of the circle.
Find the radius. If your answer is not an integer, express it in radical form.
Write an equation for the circle.

Respuesta :

The first thing we must do for this case is to use the formula of the midpoint to find the center of the circle.
 We have then:
 [tex]C = ( \frac{x1 + x2}{2} , \frac{y1 + y2}{2}) [/tex]
 Substituting values we have:
 [tex]C = ( \frac{-6 + 2}{2} , \frac{-8 + 10}{2}) [/tex]
 [tex]C = ( \frac{-4}{2} , \frac{2}{2}) [/tex]
 [tex]C = (-2, 1)[/tex]
 We are now looking for the radius of the circle. For this, we use the formula of distance between points.
 We have then:
 [tex]r = \sqrt{(x2-x1)^2 + (y2-y1)^2} [/tex]
 Substituting values we have:
 [tex]r = \sqrt{(2-(-2))^2 + (10-1)^2} [/tex]
 [tex]r = \sqrt{(4)^2 + (9)^2} [/tex]
 [tex]r = \sqrt{16 + 81} [/tex]
 [tex]r = \sqrt{97} [/tex]
 We now write the standard equation of the circle:
 [tex](x-xo)^2 + (y-yo)^2 = r^2[/tex]
 Substituting values we have:
 [tex](x+2)^2 + (y-1)^2 = 97[/tex]