Answer:
The speed of the boat in still water is 10 miles / hour
Step-by-step explanation:
The trip there, and the trip back are the same -- 30 miles
Let the rate of the boat = x
Let the rate of the water = y
30 = 2*(x + y)
30 = 6*(x - y)
Divide the top equation by 2
Divide the bottom equation by 6
15 = x + y
<u>5 = x - y </u> Add the equations together.
20 = 2x Divide by 2
20/2 = x
x = 10
Answer:
i think it is 3
Step-by-step explanation:
i drawed a circle and put it into sections
then i saw that to get the 40 degree angle i have to divide it for times to make 8 parts
then i did 12 divided by 4 because divide the circle four time
when i did 12/4 i got 3
and if i am correct
thats the answer
Answer:
<em>4 seconds, 256 ft</em>
Step-by-step explanation:
First, we'll go through what needs to be done. Then we'll do it.
When h is 0, the fireworks is at a height of 0, or ground level. That happens before it is launched, at time 0 and when it falls back to the ground after going up and down. We let h = 0, and solve for t. We get t = 0, and another value for t which is when it hits the ground on the way down. The midpoint between the two times of height zero is the time at which maximum height is reached. Then we input the maximum height time into the equation and find h, the maximum height.
Now we'll solve it. First, we set the height equation equal to zero and solve for t.
-16t^2 + 128t = 0
-16t(t - 8) = 0
t = 0 or t - 8 = 0
t = 0 or t = 8
The height is zero at t = 0 seconds and at t = 8 seconds.
Maximum height is reached at the midpoint of the two times above.
(0 + 8)/2 = 8/2 = 4.
The firework explodes at 4 seconds.
Now we find the height at 4 seconds which is the maximum height.
h = -16t^2 + 128t
h = -16(4^2) + 128(4)
h = -256 + 512
h = 256
The firework explodes at a height of 256 ft.
A linear pair mean that the angles are adjacent (side by side) to each other and that they are supplementary (sum of their angles is 180 degrees). Thus, the angles should form a straight angle or an angle with a measure of 180 degrees.