SOLUTION: Thomas is thinking of a number. He knows that the product of 5 less than twice his number and 3 more than his number is 13 What is his number?

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Question 460277: Thomas is thinking of a number. He knows that the product of 5 less than twice his number and 3 more than his number is 13 What is his number?
Answer by JimboP1977(311) About Me  (Show Source):
You can put this solution on YOUR website!
Let x be the number Thomas is thinking of
%282x-5%29+%2A+%28x%2B3%29+=+13
Multiply the left side to give
2x%5E2%2B6x-5x-15+=13
2x%5E2+%2Bx-15+=13+
(divide both sides by 2.)
x%5E2%2B%28x%2F2%29-%2815%2F2%29+=+%2813%2F2%29

x%5E2%2B%28x%2F2%29+=+%2813%2F2%29+%2B+%2815%2F2%29+=+%2828%2F2%29+=+14

%28x%2B%281%2F4%29%29%5E2%29+-+%281%2F16%29+=+14

%28x%2B%281%2F4%29%29%5E2%29++=+14%2B+%281%2F16%29+=+225%2F16

x%2B%281%2F4%29++=++%28225%2F16%29%5E%281%2F2%29


x%2B%281%2F4%29+=+%2815%2F4%29
Or
x%2B%281%2F4%29+=+-%2815%2F4%29
So
x+=+3.5 Or x=-4