Answer: Choice C and Choice D
========================================================
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.
Answer:
answer is a. corresponding angles
Subtraction then division is the answer .
I hope it is useful to you and you mark it as brainliest ,what do you say
the question in English
50 t-shirts were sold at 10€ each. What benefit was obtained if the t-shirts were bought at 7€ each?
Let
x---------> the benefit in euros
we know that




therefore
<u>the answer is</u>
The benefit is equal to 
Answer: standard time
Step-by-step explanation:
4 times zones one hour apart