9514 1404 393
Answer:
256 feet
Step-by-step explanation:
The vertex of the quadratic ax^2 +bx +c is found at x=-b/(2a). This means the time at which the rocket reaches it maximum height is ...
t = -128/(2(-16)) = 4 . . . . seconds
Evaluating h at t=4 gives the maximum height:
h = -16(4^2) +128(4) = -256 +512 = 256
The maximum height of the rocket is 256 feet.
_____
If you can read this value from "the graph at the left," you can save yourself some computation.
One-half a number (x) is equal to 14.
One-half: 1/2
a number x: multiplied by x
is equal to: =
1/2x = 14
If you were going to solve for it, divide both sides by 1/2.
x = 28
The answer you seek is 15 and -4. 15*-4=-60 and 15-4=11.