Answer:
x=7
Step-by-step explanation:
3x-9=12
add 9 to both sides
3x=21
divide both sides by 3
x=7
The perimeter is 38.4 inches
I believe it is A. Hope this helps.
Answer:

Step-by-step explanation:
Ok, so first substitute x for 4 in
"g(x) = 5x + 1", and x for 3 in
"k(x) = 2/x + 2x". Now you got:
g(4) = 5(4) + 1
k(3) = 2/(3) + 2(3)
Now you can solve each individually.
g(4) = 5 × 4 = 20
20 + 1 = 21
g(4) = 21
k(3) = 2 × 3 = 6
6 + 2/3 = 6 2/3
k(3) = 6 2/3
g(4) + k(3) = 21 + 6 2/3 = <u>27 2/3</u>
Hope this helps :)
Answer: The rocket will reach its max after 4 seconds
Step-by-step explanation:
Hi, to find the maximum height, we have to set the first derivative of the equation equal to zero.
y=-16x^2+128x+136
0 = (2)-16x +128
0= -32x+128
Solving for x:
32x = 128
x = 128/32
x = 4 seconds
The rocket will reach its max after 4 seconds
Feel free to ask for more if needed or if you did not understand something.