SOLUTION: 7^x-3/4=Square root of 6 PLEASE HELP! THANKS!

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Question 112361: 7^x-3/4=Square root of 6
PLEASE HELP! THANKS!

Answer by bucky(2189) About Me  (Show Source):
You can put this solution on YOUR website!
Given:
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7%5Ex-3%2F4+=+sqrt%286%29
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Get rid of the -3%2F4 on the left side by adding 3%2F4 to both sides to get:
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7%5Ex+=+3%2F4+%2B+sqrt%286%29
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The right side of this equation is just a number. We can find that number using a calculator.
First, the fraction 3%2F4 has a decimal equivalent of 0.75. (You can find that by using
a calculator to divide 4 (the denominator) into 3 (the numerator) and the calculator
will give you the answer of 0.75
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Then you can use a calculator to find sqrt%286%29. The answer will be 2.449489743.
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So the right side of the equation is 0.75 + 2.449489743 = 3.199489743
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Therefore the equation is now:
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7%5Ex+=+3.199489743
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You can solve this equation by taking the log to the base 10 of both sides to make the
equation become:
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log%2810%2C7%5Ex%29+=+log%2810%2C3.199489743%29
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On the right side you can use a calculator to find log(3.199489743). This log is 0.505080722.
Substitute this value for the right side and the equation becomes:
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log%2810%2C7%5Ex%29+=+0.505080722
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When you take the log of a quantity raised to an exponent, you can bring the exponent out
as a multiplier of the log. This means that on the left side of the equation, the exponent
x can be brought out as the multiplier of the log to give:
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x%2Alog%2810%2C7%29+=+0.505080722
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Use a calculator to find log%2810%2C7%29. If you do you will find that it is 0.84509804.
Substitute this for the log and the equation becomes:
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x%2A0.84509804+=+0.505080722
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Solve for x by dividing both sides of this equation to get:
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x+=+0.505080722%2F0.84509804+=+0.597659322
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You can check this answer by using a calculator to raise 7 to the exponent 0.597659322
If you do, you will find that the answer is 3.199489741. Take 3/4 (or 0.75) from this
and you get that the left side of the original equation is 2.449489741. How does this left
side compare with sqrt%286%29 which is the right side of the original equation?
As we found before, sqrt%286%29+=+2.449489743 ... close enough. So the answer of x = 0.597659322
is correct.
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Hope this helps you to understand the problem.
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