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4 years ago

Want is the solution? 21 = 42 - 3rA. r = -8B. r = -7 C. r = 7D. r = 8

Mathematics

1 answer:

VMariaS [17]4 years ago

3 0

21 = 42 - 3r
-21 = -3r
r = 7

So C.

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3 years ago

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