9514 1404 393
Answer:
68.6 m/s
Step-by-step explanation:
The speed at a given time is the derivative of the height at that time.
dh/dt = -9.8t
At t=7, the speed is ...
-9.8(7) = -68.6 . . . . . meters per second (downward)
The speed is 68.6 meters per second.
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<em>Additional comment</em>
Height is considered to be positive in the up direction, so velocity and acceleration are also positive in the up direction. The derivative of height will be the velocity. Its negative sign in this case indicates the object is moving in the downward direction. The speed is the magnitude (absolute value) of the velocity.
Answer:
Monday: 2 hours
Tuesday: 7 miles
Thursday: 27 miles
Friday: 2 hours
Step-by-step explanation:
Monday: 16 divided by 8 = 2
Tuesday: 21 divided by 3 = 7
Thursday: 9 x 3 = 27
Friday: 16 divided by 8 = 2
I hoped this helped
Answer:
Fred = 31
Natalie = 15
Step-by-step explanation:
We have Natalie and Fred's whos age are unknown, we know that when added, their ages equal 46. While when multiplied with Natalie's age 4 times, their ages is 91.
Create two systems :
F = Fred
N = Natalie
F + N = 46
4N + F = 91
We can change the first equation to Natalie's age alone :
N = 46 - F
Now substitute this into the second equation :
4(46 - F) + F = 91
Distribute :
184 - 4F + F = 91
Subtract 184 from both sides :
-4F + F = -93
Add like terms :
-3F = -93
Divide -3 from both sides :
F = 31
Therefore, Fred is 31 years old. Now replace his age in the first equation :
31 + N = 46
46 - 31
15
Therefore, Natalie is 15 years old.
No; the 75% off sign implies that he is lowering the price, when he actually wants to increase the price.
