SOLUTION: The lenght of a reactangle is 9 cm more than four times the width. The area of the rectangle is 198 cm2. Find the lenght and width

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Question 1017898: The lenght of a reactangle is 9 cm more than four times the width. The area of the rectangle is 198 cm2. Find the lenght and width
Found 2 solutions by Cromlix, KMST:
Answer by Cromlix(4381) About Me  (Show Source):
You can put this solution on YOUR website!
Hi there,
Make width = x
Length = (4x + 9)
Area = Width x Length
198 = x(4x + 9)
198 = 4x^2 + 9x
4x^2 + 9x - 198 = 0
(4x + 33)(x - 6) = 0
4x + 33 = 0
4x = -33
x = -33/4 (Disregard as negative)
x - 6 = 0
x = 6
Width = 6 cm
Length = 33 cm
Area = 6 x 33 = 198 cm^2
Hope this helps :-)

Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
Once we have x%284x%2B9%29=198 ,
we can find the answer the fifth grader's way,
much to the dismay of the algebra teacher who wants to see quadratic equations mentioned.
We can just list factors of 198 ,
198=1%2A198
198=2%2A99
198=3%2A66
198=6%2A33
198=9%2A22
198=11=18 ,
and look for a product pair that could be x%284x%2B9%29 .
9%2A22 is too far down because 22%3C4%2A9=36 .
Could it be that x=6 ?
If x=6, then 4x%2B9=4%2A6%2B9=24%2B9=33 .
So, system%28x=6%2C4x%2B9=33%29 ;
the length is 33cm and the width is 6cm.