S SCSmith New member Joined Oct 25, 2005 Messages 29 Oct 25, 2005 #1 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?
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?
S soroban Elite Member Joined Jan 28, 2005 Messages 5,586 Oct 25, 2005 #2 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! Click to expand... You had: .8x - 8 .= .8x + 3 Subtract 8x from both sides: .-8 .= .3 . ? We have a false statement. .The equation has no solution.
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! Click to expand... You had: .8x - 8 .= .8x + 3 Subtract 8x from both sides: .-8 .= .3 . ? We have a false statement. .The equation has no solution.
D Denis Senior Member Joined Feb 17, 2004 Messages 1,706 Oct 25, 2005 #3 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 Click to expand... Perhaps the 2x on the right is 2 (typo) ?
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 Click to expand... Perhaps the 2x on the right is 2 (typo) ?
