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Find the angle of intersection when the line through the points $(3,4)$ and $(-5,0)$ intersects the line through $(0,0)$ and $(-5,0)$.

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please consult our FAQ item on how to ask homework questions. In particular, please do not ask questions in the imperative, and please show your work. – Willie Wong Apr 23 '11 at 12:44

So we have points (3,4) and (-5,0) . Its equation of line would be 2y = x + 5

The other is (0,0) and (-5,0) . Its equation would be y = 0

Thus it is the x axis.

So basically since we observe that (-5,0) is the intersection point the question is to calculate the slope of second line..

Thus we get tan( theta ) = 1/2

and get theta = tan inverse(1/2) to get the acute angle of intersection....

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