Do I have the Right solution?

SCSmith

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Joined
Oct 25, 2005
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29
4/5(10x + 15) - 20 = 2x + 3/4(8x + 4)
40/5x + 12 - 20 = 2x + 6x + 3
8x + 12 - 20 = 8x + 3
8x - 8 = 8x + 3
x = 11

When I substitute 11 for x I get the wrong solution. Am I doing something wrong?
 
Heloo, SCSmith!

(4/5)(10x + 15) - 20 = 2x + (3/4)(8x + 4)
8x + 12 - 20 = 2x + 6x + 3
8x - 8 = 8x + 3
x = 11 . <--- here!
You had: .8x - 8 .= .8x + 3

Subtract 8x from both sides: .-8 .= .3 . ?

We have a false statement. .The equation has no solution.
 
SCSmith said:
4/5(10x + 15) - 20 = 2x + 3/4(8x + 4)
40/5x + 12 - 20 = 2x + 6x + 3
8x + 12 - 20 = 8x + 3
8x - 8 = 8x + 3
x = 11
Perhaps the 2x on the right is 2 (typo) ?
 
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