SOLUTION: How do I find out how much the 'a' is worth in "5a-2 = 3a-7" ??

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Question 139818: How do I find out how much the 'a' is worth in "5a-2 = 3a-7" ??
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
How do I find out how much the 'a' is worth in "5a-2 = 3a-7" ??
:
Perform some simple algebra operations to get "a" on the left by itself:
5a - 2 = 3a - 7
:
add 2 to both sides (gets rid of the -2 on the left):
5a = 3a - 7 + 2
:
5a = 3a - 5
:
Subtract 3a from both sides (gets rid of the 3a on the right)
5a - 3a = -5
:
2a = -5
:
divide both sides by 2, (gives you 1a or just a)
a = %28-5%29%2F2
a = -2.5
:
:
Prove to yourself that this is, in fact, true;
substitute -2.5 for a in the original equation:
5(-2.5) - 2 = 3(-2.5) - 7
-12.5 - 2 = -7.5 - 7
-14.5 = -14.5; equality reigns, so it is true