I believe you would do the feet ,130, divided by the minutes ,35, to get how many feet per minute. It would get you a never ending decimal of 3.714285. So every minute he would drop about 4 feet. You will have to put it how it says to for what your answering is. If it says round to the whole number then he would drop 4 feet, but I hope this helps you in any way :)
1. (3 + xz)(–3 + xz)
2. (y² – xy)(y² + xy)
3. (64y2 + x2)(–x2 + 64y2)
Explanation
The difference of 2 squares is in the form (a+b)(a-c).
(3 + xz)(–3 + xz) = (3 + xz)(xz -3)
= (xz + 3)(xz - 3)
= x²y²-3xy+3xy-9
=x²y² - 3²
(y² – xy)(y² + xy) = y⁴+xy³-xy³-x²y²
= y⁴ - x²y²
(64y2 + x2)(–x2 + 64y2)= (64y²+x²)(64y²-x²)
= 4096y⁴-64y²x²+64y²x²-x⁴
= 4096y⁴ - x⁴
Answer: Choice C and Choice D
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Explanation:
- Choice A doesn't work because it the $1 should be $7 instead.
- Choice B doesn't work because it should be Elena spending $7 total on 3 notebooks and a $1 pen. The x is the amount per notebook.
- Choice C does work. If x is the number of grapes Noah gives each friend, then 3x is the total amount Noah gives over. Then 3x+1 is the number of grapes total. That +1 at the end is the grape Noah eats. We end up with 3x+1 = 7 because Noah starts off with 7 grapes.
- Choice D works also. The x is the number of hours for math, science and history each. So 3x is the combined time of those three classes. Add on 1 to get 3x+1 to represent all 7 hours, ie 3x+1 = 7.
- Choice E does not work. If it was her spending $7 on 3 markers and a $1 pen, then it would work.
