Question

I need help asap worth 100pts

Answer 1

Answer:

Part (a)

It depends how your calculator calculates quadratic regressions.

For my calculator:

• Go to Statistics menu
• Select quadratic regression: y=a+bx+cx²
• Input the x and y values from the given table
• Go to options and select regression calc

a = 1.177142857 = 1.18 (nearest hundredth)

b = 42.22257143 = 42.22 (nearest hundredth)

c = -12.87142857 = -12.87 (nearest hundredth)

⇒ y = 1.18 + 42.22x - 12.87x²

Therefore, the quadratic regression equation in standard form is:

$y = -12.87x^2+ 42.22x + 1.18$

Part (b)

To estimate the height of the rocket after 5 seconds, input x = 5 into the regression equation:

$\implies -12.87(5)^2+ 42.22(5) + 1.18=-109.47$

As this gives us a negative value, this means that the rocket would have come back to the ground before 5 s.  Therefore, the height of the rocket at 5 s will be 0 ft.

(see attached graph → the rocket will hit the ground at approx 3.3 s)