Answer:

Step-by-step explanation:
Given

Required
Find f(x - 4)
Substitute x - 4 for x

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Collect like terms


Answer:
It is B. Commutative Property of Addition. I selected d from the other answer and it was wrong, just trust me it b. Commutative.
Hope this helps you.
Answer:
Your question is incomplete pleasegove the real question.
Step-by-step explanation:
Answer:
Mary = 24
Chau = 15
David = 48
Step-by-step explanation:
The formula is
Mary + Chau + David = 87
And we know that
Chau = Mary - 9
David = Mary * 2
So when we fill this in
Mary + Mary - 9 + Mary * 2 = 87
4Mary - 9 = 87
4Mary = 96
Mary = 24
Chau = Mary - 9 = 15
David = Mary * 2 = 48