SOLUTION: need help seeing if these two expressions are equivalent -2(3m-7) 14-6m You put -1 in for M

Algebra ->  Expressions -> SOLUTION: need help seeing if these two expressions are equivalent -2(3m-7) 14-6m You put -1 in for M      Log On


   

Question 522756: need help seeing if these two expressions are equivalent
-2(3m-7) 14-6m
You put -1 in for M
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
need help seeing if these two expressions are equivalent
-2(3m-7) 14-6m
You put -1 in for M
-----------------
-2(3m-7) = -2*3m + -2*(-7) = -6m + 14
= 14 - 6m, so they're equal.
--------------
Testing with any number is not proof they're equal.
Testing with a number and finding them not equal is sufficient to disprove it, but it's not a sufficient test to prove that they're equal for ALL values of m.
---------