Answer:
[tex]2x^2+12x[/tex]
Step-by-step explanation:
Dimensions of Poster 1:
- Length = x inches
- Width = (x + 5) inches
Dimensions of Poster 2:
- Length = x inches
- Width = (x + 7) inches
The posters can be modeled as rectangles.
[tex]\boxed{\textsf{Area of a rectangle}=\sf length \times width}[/tex]
Therefore, the expressions for the area of each poster are:
[tex]\implies \textsf{Area of Poster 1}=x(x+5)[/tex]
[tex]\implies \textsf{Area of Poster 2}=x(x+7)[/tex]
Therefore, the expression that represents the area of the wall that the posters will cover is the sum of the expressions of the areas of the individual posters:
[tex]\begin{aligned}\textsf{Area of wall posters will cover}&=\textsf{Area of Poster 1}+\textsf{Area of Poster 2}\\& = x(x+5)+x(x+7)\\&=x^2+5x+x^2+7x\\&=x^2+x^2+5x+7x\\&=2x^2+12x\end{aligned}[/tex]