SOLUTION: use 5 step problem solving. The product of two facing pages is 420. Find the page numbers

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Question 282389: use 5 step problem solving. The product of two facing pages is 420. Find the page numbers
Found 2 solutions by nerdybill, Alan3354:
Answer by nerdybill(7384) About Me  (Show Source):
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use 5 step problem solving. The product of two facing pages is 420. Find the page numbers
.
Let x = page on the left
then (because it is the next page)
x+1 = page on the right
.
From:"product of two facing pages is 420" we get our equation:
x(x+1) = 420
x^2 + x = 420
x^2 + x - 420 = 0
Factoring the left:
(x+21)(x-20) = 0
x = {-21, 20}
We can toss out the -21 (can't have a negative page number) so we are left with:
x = 20
Therefore, the two page numbers are: 20 and 21

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
sqrt%28420%29 = 20.49.....
--> 20 & 21