Fan and medal.

A sandbag was thrown downward from a building. The function f(t) = -16t2 - 64t + 512 shows the height f(t), in feet, of the sandbag after t seconds.

Part A: Factor the function f(t) and use the factors to interpret the meaning of the x-intercept of the function. (4 points)

Part B: Complete the square of the expression for f(x) to determine the vertex of the graph of f(x). Would this be a maximum or minimum on the graph? (4 points)

Part C: Use your answer in part B to determine the axis of symmetry for f(x)? (2 points)

Question

Fan and medal.

A sandbag was thrown downward from a building. The function f(t) = -16t2 - 64t + 512 shows the height f(t), in feet, of the sandbag after t seconds.

Part A: Factor the function f(t) and use the factors to interpret the meaning of the x-intercept of the function. (4 points)

Part B: Complete the square of the expression for f(x) to determine the vertex of the graph of f(x). Would this be a maximum or minimum on the graph? (4 points)

Part C: Use your answer in part B to determine the axis of symmetry for f(x)? (2 points)

vocaloid · Answer

well, first off, do you understand how to factor a quadratic expression?

desiraem · Answer

No honestly.

vocaloid · Answer

Hmm, that makes things a bit more difficult...I can try to show you how to do it

vocaloid · Answer

-16t2 - 64t + 512 = -16(t^2+4t-32), are you with me so far?

desiraem · Answer

no?

vocaloid · Answer

all I did was "take out" -16 from each term and rewrote the expression

vocaloid · Answer

do you agree that 4 + 2 = 2(2 + 1)?

desiraem · Answer

yes.

vocaloid · Answer

well, I did the same thing with -16t2 - 64t + 512

-16t2 - 64t + 512 = -16(t^2+4t-32)

vocaloid · Answer

if you multiply -16(t^2+4t-32) out, you'll get -16t2 - 64t + 512

desiraem · Answer

okay i got it.

vocaloid · Answer

great! Let's keep going: t^2+4t-32 = (t+8)(t-4)

desiraem · Answer

okay

desiraem · Answer

it's fine, but thanks anyway.