Algebra-1

Step 1: Distribute the parentheses.
(7m − 2n + 5) + (3m + 4n − 8) is the same as 7m − 2n + 5 + 3m + 4n − 8.

Step 2: Combine like terms.

Combine the terms with m: 7m + 3m = 10m.
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