The line y=9x-4 intersects the quadratic function y=x^2+7x at one point. What are the coordinates of the point of intersection?

1 answer

that would be where

9x-4 = x^2+7x
x^2-2x+4 = 0

That has no real solutions, so I suspect a typo. See that the graphs do not intersect:

http://www.wolframalpha.com/input/?i=plot+y%3D9x-4+%2C+y+%3D+x^2%2B7x

Now, the line y=9x+4 does intersect the parabola.