Search All of the Math Forum:
Views expressed in these public forums are not endorsed by
NCTM or The Math Forum.



College Algebra Question
Posted:
Sep 18, 2011 11:33 AM


Hi Everyone,
Here is a problem that I have been working on. I cannot figure out where I am going wrong. I've typed out the problem and showed all work/steps on how to solve it. Can you please help me find my error and how to fix it? I would greatly appreciate it. Thank you!
Original problem: "The dimensions of a rectangle are such that its length is 9in more than its width. If the length were doubled and if the width were decreased by 4in, the area would be increased by 110in^2. What are the length and width of the rectangle?"
My work:
A+110=2(x+9)(x4)
Multiplied the first term by 2 A+110=(2x+18)(x4)
Using FOIL I multiplied the terms together A+110=2x^28x+18x72
Combined like terms A+110=2x^2+10x72
Subtract 110 from both sides A=2x^2+10x182
This the point in which I am stuck. The numbers that multiply together to make 182 is (2,91) (7,26) (13,14)
A=(2x14)(x+13)
when factored together you get 2x^2+26x14x182 when like terms are combined 2x^2+12x182, this is not right.
Thanks in advance for your help.



