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.
Both A and C are used within this problem. Distributing happens in the first and second step. Also, Inverse operations are used in nearly every step that is solving.
Answer:
6 and 21 meters long
Step-by-step explanation:
You make an equation from what you got (there are 2 widths and 2 lengths)
2(4w-3)+2w=54---->10w-6=54---> 10w=60 ----> w=6 ---> plug in the rest and you get 21 as the length.
or... make W+L=28 and guess and check!!! takes longer but works!
Answer:
<h3>
(6, 3)</h3>
Step-by-step explanation:
Translation right (or left) means change of the x-coordinate.
Translation down (or up) means change of the y-coordinate.
(3, 8) → (3+3, 8-5) = (6, 3)
Let the age of devaughn be x and Sydney be y.
Then,x+y=45
x+5=y
y=x+5
here,
put y=x+y in x+y=45
then,
x+y=45
x+x+5=45
2x=40
x=20
now,
y=x+5
y=20+5
y=25