Answer:
t≈8.0927
Step-by-step explanation:
h(t) = -16t^2 + 128t +12
We want to find when h(t) is zero ( or when it hits the ground)
0 = -16t^2 + 128t +12
Completing the square
Subtract 12 from each side
-12 = -16t^2 + 128t
Divide each side by -16
-12/-16 = -16/-16t^2 + 128/-16t
3/4 = t^2 -8t
Take the coefficient of t and divide it by 8
-8/2 = -4
Then square it
(-4) ^2 = 16
Add 16 to each side
16+3/4 = t^2 -8t+16
64/4 + 3/4= (t-4)^2
67/4 = (t-4)^2
Take the square root of each side
±sqrt(67/4) =sqrt( (t-4)^2)
±1/2sqrt(67) = (t-4)
Add 4 to each side
4 ±1/2sqrt(67) = t
The approximate values for t are
t≈-0.092676
t≈8.0927
The first is before the rocket is launched so the only valid answer is the second one
Answer:
380; 5% increase is 399
39; 33% decrease 26.13
48; 15% increase 55.2
3,000; 325% increase 12,750
160; 20% decrease 128
Step-by-step explanation:
Answer:
1256000
Step-by-step explanation:
My example:
Find the radius of the sphere by substituting 4.5? ft^3 for V in the formula in Step 1 to get: V=4.5? cubic feet.= (4/3)?(r^3)
Multiply each side of the equation by 3 and the equation becomes: 13.5 ? cubic feet =4?(r^3)
Divide both sides of the equation by 4? in Step 4 to solve for the radius of the sphere. To get: (13.5? cubic feet)/(4?) =(4? )(r^3)/ (4?), which then becomes: 3.38 cubic feet= (r^3)
Use the calculator to find the cubic root of 3.38 and subsequently the value of the radius “r” in feet. Find the function key designated for cubic roots, press this key and then enter the value 3.38. You find that the radius is 1.50 ft. You can also use an online calculator for this calculation (see the Resources).
Substitute 1.50 ft. in the formula for SA= 4?(r^2) found in Step 1. To find: SA = 4?(1.50^2) = 4?(1.50X1.50) is equal to 9? square ft.
Substituting the value for pi= ?= 3.14 in the answer 9? square ft., you find that the surface area is 28.26 square ft. To solve these types of problems, you need to know the formulas for both surface area and volume.
That would be 6 divided by 8 so the answer is 0.75 hope that helped!!
