Parallel line means they have the same slope
y = mx + b
where m = slope
y = -3 + 4
here the slope is negative 3
y = -3x + b
plug in (4, 8)
8 = -3(4) + b
b = 8 + 12
b = 20
The answer is y = -3x + 20
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.
A.) y = ut - 1/2gt^2 + 12
y = 6t - 1/2(9.8)t^2 + 12
y = 6t - 4.9t^2 + 12
b.) The y-intercept is 12
c.) The y-intercept represent the height of the ball at time t = 0
d.) At the time the ball reaches the ground, y = 0
-4.9t^2 + 6t + 12 = 0
t = 2.29 seconds
Therefore, it took the ball 2.29 seconds to reach the ground.