SOLUTION: If y(x-1)=z then x= please help me understand this. Kevin.

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Question 456729: If y(x-1)=z then x=
please help me understand this.
Kevin.

Answer by bucky(2189) About Me  (Show Source):
You can put this solution on YOUR website!
What the question is asking you to do is to solve for x. This means that you will need to get x on one side of the equation and everything else on the other side.
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Notice that within the parentheses you have the quantity x - 1. This entire quantity is multiplied by y.
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Suppose that you begin by dividing both sides of the equation by y to get rid of the y on the left side. When you do this division you get:
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x-1+=+z%2Fy
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Now get rid of the -1 on the left side by adding +1 to both sides and you have the answer of:
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x+=+z%2Fy%2B1
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You could also have begun the problem by multiplying out the left side ... multiplying y times (x-1). If you do that, the equation becomes:
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yx+-+y+=+z
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Next get rid of the -y term on the left side by adding +y to both sides. The result is:
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yx+=+z%2By
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Now get rid of the y on the left side by dividing both sides by y to get:
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x+=+%28z%2By%29%2Fy
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Simplify the right by dividing both terms in the numerator by y:
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x+=+z%2Fy%2By%2Fy
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And finally, recognize that y%2Fy=1. Substitute this equivalent value into the right side of the equation and you have:
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x+=+z%2Fy%2B1
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And this is the same answer that we got the first time. It just took a little more work.
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Hope this helps you to understand the problem better, Kevin.