SOLUTION: An equation of the line tangent to the graph of 25=x^2+y^2 at the point (3,4) is

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Question 767039: An equation of the line tangent to the graph of 25=x^2+y^2 at the point (3,4) is
Answer by reviewermath(1029) About Me  (Show Source):
You can put this solution on YOUR website!
Q:
An equation of the line tangent to the graph of 25=x%5E2%2By%5E2 at the point (3,4) is
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A:
Let m%5B1%5D be the slope of the line joining the center of the circle and the point of tangency.
m%5B1%5D = %284+-+0%29%2F%283+-+0%29 = 4%2F3
The slope of the tangent line is equal to %28-1%29%2Fm%5B1%5D = -3%2F4.
The equation of the tangent line is y+-+4+=+%28-3%2F4%29%28x+-+3%29.
ANSWER: highlight%28y+=+%28-3%2F4%29x+%2B+25%2F4%29.
Here's the graph of the tangent line and the circle: