Question 746874
a circle of radius 5 with center at (2,7) has equation (x-2)squared+(y-7)squared=25. at which points does the line y=3 intersect with the circle 
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{{{(x-2)^2 + (y-7)^2 = 25}}}
Sub 3 for y
{{{(x-2)^2 + (3-7)^2 = 25}}}
{{{(x-2)^2 + 16 = 25}}}
{{{(x-2)^2 = 9}}}
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x - 2 = 3
x = 5 --> (5,3)
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x - 2 = -3
x = -1 --> (-1,3)