SOLUTION: I have a math problem I don't understand how to do it 5x+2x-9=40

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Question 529860: I have a math problem I don't understand how to do it 5x+2x-9=40
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
5x + 2x - 9 = 40
combine like terms, add the x's
7x - 9 = 40
add 9 to both sides
7x - 9 + 9 = 40 + 9
7x = 49
divide both sides by 7
x = 49%2F7
x = 7
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Check solution in original equation
5x + 2x - 9 = 40
5(7) + 2(7) - 9 = 40
35 + 14 - 9 = 40
49 - 9 = 40; confirms our solution of x=7