SOLUTION: please solve for x : {{{100^(x^2)=10^(5x-3)}}}

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Question 131921: please
solve for x : 100%5E%28x%5E2%29=10%5E%285x-3%29

Answer by bucky(2189) About Me  (Show Source):
You can put this solution on YOUR website!
Given to solve for x:
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100%5E%28x%5E2%29=10%5E%285x-3%29
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Take the base 10 logarithm of both sides:
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log%2810%2C100%5E%28x%5E2%29%29+=+log%2810%2C10%5E%285x-3%29%29
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Apply the rule of logarithms that says an exponent comes out as the multiplier of the logarithm.
When you apply that rule, the problem becomes:
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%28x%5E2%29%2Alog%2810%2C100%29+=+%285x-3%29log%2810%2C10%29
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But your calculator will tell you that log%2810%2C100%29+=+2 and log%2810%2C10%29+=+1
Make these two substitutions into the equation and it becomes:
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%28x%5E2%29%2A2+=+%285x+-+3%29%2A1
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which simplifies to:
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2x%5E2+=+5x+-+3
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subtract 5x - 3 from both sides to get the equation into the standard form of:
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2x%5E2+-+5x+%2B+3+=+0
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The left side of this equation factors to give:
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%28x+-1%29%2A%282x-3%29+=+0
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Notice that this equation will be true if either of the two factors is equal to zero ... because
a multiplication by zero on the left side makes the entire left side equal to zero and
therefore equal to the right side.
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So either x-1+=+0 or 2x+-+3=+0
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Solve these two equations. From x-1+=+0 you can see that x+=+1 and from 2x-3=+0
you get x+=+3%2F2+=+1.5
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Therefore, the two answers to this problem are x = 1 and x = 1.5
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Hope this helps you to understand the problem and how it can be worked to get the answer.
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