SOLUTION: what is "x" in this equation?: {{{3(x-5)+7=16}}}

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Question 118560: what is "x" in this equation?: 3%28x-5%29%2B7=16
Answer by bucky(2189) About Me  (Show Source):
You can put this solution on YOUR website!
Given:
.
3(x - 5) + 7 = 16
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to solve, first do the distributed multiplication on the left side by multiplying 3 times
each of the terms inside the parentheses. When you do that multiplication, the equation
becomes:
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3x - 15 + 7 = 16
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On the left side combine the -15 and the +7 to get -8 ... making the equation:
.
3x - 8 = 16
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Get rid of the -8 on the left side by adding 8 to both sides. On the left side the -8 adds to
+8 to cancel out. On the right side the 16 and + 8 adds to 24 and the resulting equation is:
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3x = 24
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Solve for x by dividing both sides of this equation by 3 to get:
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x = 24/3 = 8
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The answer is x = 8
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Check by returning to the original equation and replacing x by 8. The original equation is:
.
3(x-5)+7=16
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Substitute 8 for x and it becomes:
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3(8 - 5) + 7 = 16
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Combine the 8 and -5 inside the parentheses to get + 3 and the equation then is:
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3(+3) + 7 = 16
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The 3 times +3 equals 9 which makes the equation:
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9 + 7 = 16
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And this is obviously true ... 9 plus 7 does equal 16. So our answer of x = 8 checks out
as being correct.
.
Hope this helps you to understand the process of solving this problem and how you can check
the answer to ensure that it is correct.
.