4 years ago

If 3y+5=7x, then 21y-49x=?

Mathematics

1 answer:

FromTheMoon [43]4 years ago

3 0

3y+5=7x

3y=7x-5

y=(7x-5)/3

...

21y-49x becomes

7(7x-5)-49x

49x-35-49x

-35

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