Im pretty sure the answer is 7.84. i got this because 7 is a whole number so it is in the whole number spot. Then, you have to get your denominator to 100. So, what times 25 equals 100? its 4. so you get 100 so whatever you do to your denominator you do to your numerator. so 21 times 4 is 84. so 84/100 is actually 7.84. Hope this helped
Answer:
The rocket's maximum height will be 1424 feet.
It will reach that height in 4 seconds.
It will reach the ground in 8 seconds.
Step-by-step explanation:
One easy way to find the peak is to find the derivative and solve for zero:
h(t) = -16t² + 128t + 1680
To find the derivative of each term in that format, you simply multiply the coefficient by the exponent, and reduce the exponent by one. In the case of terms with no variable, they disappear. That gives us:
h'(t) = -32t + 128
This derivative describes the rate of change of h with respect to t, so to find the peak, we simply need to solve it for zero:
0 = -32t + 128
32t = 128
t = 4
So the maximum height occurs when t = 4. Let's plug it in to the original equation:
h(t) = -16t² + 128t + 1680
h(4) = -256 + 512 + 1680
h(4) = 1424
So the rocket's maxiumum height is 1424 feet.
And we've already answered the second question, it happens at 4 seconds.
Also, the amount of time going up will be the same as the amount of time going down, which means that it will reach the ground in twice that time, or 8 seconds.
Answer: Distributive hope this helps.
Step-by-step explanation:
Answer:
6 book purchases.
Step-by-step explanation:
As the bookstore sells frequent buyers discount cards at $ 12, which make the books that usually cost $ 9 cost $ 7, to determine from how many books a card-holder and a common buyer will spend the same amount of money is necessary perform the following calculation:
9 - 7 = 2
12/2 = 6
Therefore, after purchasing 6 books, both categories of buyers will have spent the same amount of money. This is verified with the following calculation:
Card holder = 12 + 7 x 6 = 54
Non-card holder = 9 x 6 = 54
