Answer:
4x^2 + 28x - 80=0
Step-by-step explanation:
(2x+4)(2x+10) = 120
1. Use FOIL (Distribute):
4x^2 + 20x +8x + 40 = 120
2. Group like terms:
4x^2 + 28x+ 40 = 120
3. Subtract 120 from both sides:
4x^2 + 28x - 80 = 0
Answer:
Option 3 - [tex]4x^2+28x-80=0[/tex]
Step-by-step explanation:
We have given,
The length of a rectangular frame is represented by the expression L=2x+4.
The width of the rectangular frame is represented by the expression B=2x+10.
The total area of a rectangular frame is A=120 square inches.
To find : Write an equation to solve for the width of a rectangular frame ?
Solution :
The area of the rectangle is given by,
[tex]\text{Area}=\text{Length}\times \text{Breadth}[/tex]
Substitute the values,
[tex]120=(2x+4)\times(2x+10)[/tex]
[tex]120=4x^2+20x+8x+40[/tex]
[tex]4x^2+28x+40-120=0[/tex]
[tex]4x^2+28x-80=0[/tex]
The required equation is [tex]4x^2+28x-80=0[/tex]
Therefore, option 3 is correct.
