16. You decide to drop a penny off the top of the Willis Tower (fromerly the Sears Tower) in Chicago, IL. The height of the penny (in feet) can be represented by the equation h= -16t2 + 1451 where t is time (in seconds).
a) How long will it take for the penny to hit the ground? Show any work that leads to your answer.

9.5 seconds.

Step-by-step explanation:

We know that the equation that represents the height of the penny as a function of time is:

h(t) = -16*t^2 + 1451

Where the height is in ft, and the time is in seconds.

a) We want to know how long takes the penny to hit the ground.

Well, the penny will hit the ground when its height is equal to zero.

Then we need to solve for t:

h(t) = 0 = -16*t^2 + 1451

0 = -16*t^2 + 1451

16*t^2 = 1451

t^2 = 1451/16 = 90.7

t = √90.7 = 9.5

This means that it takes 9.5 seconds to hit the ground.

9.5 seconds

Step-by-step explanation:you subtract

3. (5x + 1) - (-10x + 6)

simplify the answer choice. combine like terms. remember to distribute the negative to the terms inside the second parenthesis. also remember that two negatives = one positive, and one of each sign = negative.

- (-10x + 6) = + 10x - 6

simplify. combine like terms:

5x + 1 + 10x - 6

5x + 10x + 1 - 6

15x - 5

∴ it is your answer

~

step-by-step explanation:

the ratio of red paint to blue paint is always 9/7. that means that, whatever x's value, (4x+12)/(4x-4) has that same ratio. so, set up an equation and cross-multiply to solve for x:

9/7 = (4x+12)/(4x-4)

9(4x-4) = 7(4x+12)

36x - 36 = 28x + 84

8x - 36 = 84

8x = 120

x = 15