Can someone let me know how to work these out. I don’t want the answer i want the method please!!

Answer:
45: you want to multiply 1/7 by 49x and then multiply 1/7 by 7y
47: you want to multiply 1/8 by 8x and then multiply 1/8 by -16
49: you want to multiply 1/10 by 100x and then multiply 1/10 by 10y
Answer:
Step-by-step explanation:
factorization, is that how u call it? S: Im not good at english
49 = 7x7, right?
and
7 = 7 x 1
then (49x + 7y) = (7*7x + 7y) = 7(7x + 1y)
7*7x = 49x
7*1y = 7y
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1*7 -----> 7(7x + 1y)
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7
Simplify 7/7 = 1
answer = 7x +y