Solving Linear-Quadratic Systems by Elimination

$$\text{Invite an Alien to Live with You Day}$$

===

Today (July 21) is Invite an Alien to Live with You Day!

A UFO beams you up late one night. But, as it turns out, the alien is a pretty cool dude. It's just looking for a place to crash for a bit. Since you have a spare room at your place you invite it to stay. The alien allows you to fly the UFO in return for your hospitality.

Your neighborhood is mapped out with the equation: $y=-0.1x^2+40$

You set the flight path of the UFO to: $y=4x+70$