Answer:
-439
Step-by-step explanation:
Think of the question as s(f(-7))
First replace x with -7 in the equation f(x)= 3x
s(-7) = 3*(-7)
s(-7) = -21
now it is s(-21)
we substitute -21 into the s(x) equation to get 
That gives you 2-441 = -439
Okay. So the bill was a total of $725, with 6% sales tax added. To find the amount of sales tax, all you have to do is multiply the amount on the bill by the percentage of tax. 725 * 6% (0.06) is 43.5. There. The sales tax was $43.50.
vi is going in the positive direction (up). (That's my choice). a (acceleration) is going in the minus direction (down). The directions could be reversed.
Givens
vi = 160 ft/s
vf = 0 (the rocket stops at the maximum height.)
a = - 9.81 m/s
t = ????
Remark
YOu have 4 parameters between the givens and what you want to solve. Only 1 equation will relate those 4. Always always list your givens with these problems so you can pick the right equation.
Equation
a = (vf - vi)/t
Solve
- 32 = (0 - 160)/t Multiply both sides by t
-32 * t = - 160 Divide by -32
t = - 160/-32
t = 5
You will also need to solve for the height to answer part B
t = 5
vi = 160 m/s
a = - 32
d = ???
d = vi*t + 1/2 a t^2
d = 160*5 + 1/2 * - 32 * 5^2
d = 800 - 400
d = 400 feet
Part B
You are at the maximum height. vi is 0 this time because you are starting to descend.
vi = 0
a = 32 m/s^2
d = 400 feet
t = ??
formula
d = vi*t + 1/2 a t^2
400 = 0 + 1/2 * 32 * t^2
400 = 16 * t^2
400/16 = t^2
t^2 = 25
t = 5 sec
The free fall takes the same amount of time to come down as it did to go up. Sort of an amazing result.
Answer:
C. (16y + 7z)
Step-by-step explanation:
9y + 11z + 7y - 4z
1. Simplify the y's: 9y + 7y = 16y
16y + 11z - 4z
2. Simplify the x's: 11z - 4z = 7z
16y + 7z
Answer: 3/4 or 75/100
Step-by-step explanation:
3 divided by 4
Answer 3/4
Ration is 3:4
Fraction is 3/4
Fraction is also 75/100
Percentage is 75%
