The shape of a roller coaster is modeled by a polynomial function, R(x). Describe how to find the x-intercepts of R(x) and how to construct a rough graph of R(x) so that the engineer can predict when there will be no change in the direction of the coaster. You may create a sample polynomial to be used in your explanations. Gets a medal!!!!

Question

xguardians · Answer

1. You can find the x-intercepts of R(x) by setting it equal to zero and solving for x.
2. You can prevent the coaster from changing direction by using a simple polynomial that is always positive (positive slope).

artemis17 · Answer

What do I set equal to zero though?

xguardians · Answer

If you have the equation of a line as y = 5x + 3
Set y = 0
0 = 5x + 3
-3 = 5x
x = -3/5
At that point the y-value is 0.

artemis17 · Answer

So to find the x-intercepts of R(x), I can set y to zero like you did?

xguardians · Answer

Yep, exactly.

artemis17 · Answer

Then all I have to do is write how to graph r(x) which basically  x=-3/5 and the y value?

xguardians · Answer

So take the previous function I had, y = 5x + 3
Then plug in the x-value we found by setting y = 0
y = 5(-3/5) + 3
y = -15/5 + 3
y = -3 + 3
y = 0
Therefore, you get zero again.

artemis17 · Answer

ohh okay!! Thank you helps a lot..