I'm just introducing myself to coordinate geometry in the xy plane of cirlces.(adsbygoogle = window.adsbygoogle || []).push({});

Here's a question i'm having trouble with:

Q11: The line with equation y=mx is a tangent to the circle with equation x^2 + y^2 - 6x - 6y + 17 = 0. Find the possible values of m.

At first i thought i'd try substituting y=mx into the curve equation, but i was still left with 2 unknowns. I don't really know what to do here. Could anyone offer some advice? Thanks.

The answer is (9 (+ or -) root 17) / 8

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# Homework Help: Coordinate geometry - circles.

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