SOLUTION: The area of a rectangle is represented by A=5x^2+102x+40. Factor the expression to find polynomials that represent the length and width of the rectangle

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: The area of a rectangle is represented by A=5x^2+102x+40. Factor the expression to find polynomials that represent the length and width of the rectangle       Log On


   

Question 1035205: The area of a rectangle is represented by A=5x^2+102x+40. Factor the expression to find polynomials that represent the length and width of the rectangle
Found 2 solutions by josgarithmetic, addingup:
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Easier to find roots to help in factoring. You might use less advanced method by splitting the 40 into combinations as
1%2A40
2%2A20
4%2A10
5%2A8

Work with those if you want to.

Roots:
%28-102%2B-+sqrt%28102%5E2-4%2A5%2A40%29%29%2F10
%28-102%2B-+sqrt%289604%29%29%2F10
%28-102%2B-+98%29%2F10
-200/10 or -4/10
-20 or -2/5

highlight%28A=5%28x%2B20%29%28x%2B2%2F5%29%29

Answer by addingup(3677) About Me  (Show Source):
You can put this solution on YOUR website!
factoring:
(x+20)(5x+2)