SOLUTION: the line y=0 is a tangent to the circle (x-8)^2 + (y-a)^2=16. find the value of a. thank you so much!!

SOLUTION: the line y=0 is a tangent to the circle (x-8)^2 + (y-a)^2=16. find the value of a. thank you so much!!

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Question 264554: the line y=0 is a tangent to the circle (x-8)^2 + (y-a)^2=16. find the value of a. thank you so much!!
Answer by Alan3354(69443) (Show Source): You can put this solution on YOUR website!
the line y=0 is a tangent to the circle (x-8)^2 + (y-a)^2=16. find the value of a.
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y=0 is the x-axis.
The radius of the circle is 4 (the square root of 16).
The center has to be 4 units from the x-axis, so
a = 4 or
a = -4

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