You can put this solution on YOUR website! for what value(s) of m is the line y = mx + 5 at a distance 4 from the origin?
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All points on a circle about the Origin with r = 4 are 4 units from the Origin.
Find the intersections of
y = mx + 5 and
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That doesn't look promising.
Try this:
The slope at any point on the circle is -x/y.
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y = mx + 5
m = (y-5)/x = -x/y
x^2 = -y^2 + 5y --> x^2 + y^2 = 5y
5y = 16
y = 3.2
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x^2 + y^2 = 16
x^2 = 16 - 3.2^2 = 5.76
x = -2.4, +2.4
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The 2 tangent points are (-2.4,3.2) and (2.4,3.2)
The y-int of y = mx + 5 is (0,5)
1 slope = (5-3.2)/2.4 = +0.75
The other is -0.75
