Answer:
y = (x+3)² - 1
Step-by-step explanation:
To complete the square take the middle term b and divide by 2. Then square the value.
Here b = 6.
So 6/2 = 3
3² = 9
Add 9 to both sides of the equation.
x² + 6x + 8 = 0
x² + 6x + 9 + 8 = 9
(x+3)² - 1 = y
Answer:
The speed from the observer is 8 mph.
Step-by-step explanation:
When the boat is going downstream with full force, its speed will be the one the oarsman can row on still water added by the flow of the river. In this case he can row the boat at speed of 3 mph, while the stream is 5 mph, so the speed from the observer standpoint is:

The speed from the observer is 8 mph.
Answer:
60 seconds, 7715 feet
Step-by-step explanation:
Plane A and B start out 615 feet apart, and we find this by subtracting the height of plane A from plane B, getting 5000-4385=615. Now we have to find how many more feet of altitude plane A is gaining per second over plane B.
To find this we subtract 45.25 from 55.5 and get 10.25 feet per second. Now to find out how many seconds until they'll be at the same altitude we simply divide 615 by 10.25, getting 60 seconds.
For the second part, to find the altitude at this point, we simply multiply the altitude gain of one of the planes per second by the time of 60 seconds to get how much altitude they gained over that time, and add it to the starting altitude. Doing this with plane B we get 45.25*60=2715, and we add that to 5000 to get the final answer of 7715.
Year 1: 7lbs x 3years= 21lbs
Year 2: 21lbs x 3years = 63lbs
Answer:
b. -1
Step-by-step explanation:
9=4a+13
-13 -13
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-4=4a
4a/-4
a=-1