3 Answers: Choice A, Choice B, Choice E
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Step-by-step explanation:
We have four copies of x in the original expression. So that accounts for the 4x. In other words, 4x = x+x+x+x. Multiplication is used for repeated addition.
Also, the other terms add to 15+5+15+5 = 20+20 = 40
Therefore, we end up with 4x+40 from choice A.
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Once we get to 4x+40, we can factor out 2 from it like so
4x+40
2*2x + 2*20
2(2x+20) which is choice B
I used the distributive property to factor. That rule is a(b+c) = ab + ac
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Choice C is not one of the answers. We can determine this fairly quickly by noting that the expression in choice C talks about a quadratic, but the original expression given to us is linear.
Choice D is a similar story to choice C.
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Choice E is another answer
This is because we have two copies of (x+15), so that gives 2(x+15)
We also have two copies of (x+5) to get 2(x+5)