Question

HELP! PLEASE! I really need help with this question!

Answer 1

Answer:

They are at the same height at 1.13 seconds.

Step-by-step explanation:

Remark

The rockets are at the same height when  f(x) = g(x) [see below] are the same. So you can equate them.

Givens

f(x) = - 16x^2 + 74x + 9

g(x) = -16x^2 + 82x              I have changed this so you don't have 2 f(x)s

Solution

• f(x) = g(x)
• -16x^2 + 74x + 9 = -16x^2 + 82x                        Add:  16x^2 to both sides
• -16x^2+16x^2+74x + 9 = -16x^2+16x^2 + 82x   Combine terms
• 74x + 9 = 82x                                                     Subtract 74x from both sides
• 74x - 74x + 9 = 82x - 74x                                  Combine
• 9 = 8x                                                                 Divide by 8
• 9/8 = 8x/8
• x = 1 1/8                                                              Convert to decimal
• x = 1.125
• x = 1.13  [rounded]