Answer:
y=-1/4x+3
Step-by-step explanation:
Note that this just produces three parametric equations:



In the

plane, this is just he parametric equation for an ellipse (as a function of u). The z is simply a linear function.
The surface is then an ellipse extruded along the z-axis. We get a elliptic cylinder.
Answer:
x = 10
Step-by-step explanation:
Q is the midpoint of PR: PQ = QR
4x + 5 = 2x + 25
2x = 20
x = 10