please show me how to solve for y (4x+y) = (x-y) thanks
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Hi Originally Posted by cornman please show me how to solve for y (4x+y) = (x-y) thanks 4x +y = x - y calculate: -4x on both sides 4x + y - 4x = x -y - 4x 0x + y = -3x - y y = -3x -y calculate: add +y on both sides y +y = -3x -y +y 2y = -3x Now divide by 2 $\displaystyle \frac{2y}{2} = \frac{-3x}{2}$ $\displaystyle y = \frac{-3x}{2}$ Ok? Cheers, Rapha
Thanks Rapha. i didnt think i could subtract terms from the parentheses. what am i missing?
Originally Posted by cornman I didnt think i could subtract terms from the parentheses. what am i missing? Yes you can, because this is a summation, not a product. These parantheses just matter, if theres another factor like 3*(4x+y) = -17*(x-y) In this case you can't just subtract 4x like 3*(4x+y) - 4x = 3*y This is horribly wrong. Not sure I didn't get your point. Rapha
Originally Posted by cornman can someone please show me the steps to solve for y for the following? (4x+y) = (x-y) thanks! $\displaystyle 4x + y = x - y$ $\displaystyle 4x = x - 2y$ $\displaystyle 3x = -2y$ $\displaystyle y = -\frac{3}{2}x$
Last edited by mr fantastic; Feb 20th 2009 at 02:34 AM. Reason: No edit - just flagging this reply as having been moved from a duplicate post
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