SOLUTION: the product of a number and 4 less than the number is 32. find the numbers

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Question 446534: the product of a number and 4 less than the number is 32. find the numbers
Answer by duckness73(47) About Me  (Show Source):
You can put this solution on YOUR website!
Let x = the first number; which means that x - 4 is the second number. Since we know the product of the two numbers is 32, that means that if you multiply them together, you get 32. Here's the equation:
x (x - 4) = 32
Let's expand the left side:
x%5E2+-+4x+=+32
And, solving for x we have:
x%5E2+-+4x+-+32+=+0
Then, factoring, we have:
x%5E2+-+4x+-+32+=+0
(x-8)(x+4) = 0
x = 8 or x = -4
In the first case, where x = 8, that would mean that x - 4 = 8 - 4 = 4. And, 8 times 4 is 32. So the pair of 8 and 4 works.
In the second case, where x = -4, that would mean that x - 4 = -4 - 4 = -8. And, -4 times -8 is again 32. So the pair -4 and -8 works.