Answer:
The area of remaining wall after the mural has been painted is [tex]46x^2+73x+15[/tex] square units.
Step-by-step explanation:
If the dimensions of a rectangle are l and w, then area of rectangle is
[tex]A=l\times w[/tex]
The dimensions of wall are (6x+7) and (8x+5). So, the area of wall is
[tex]A_1=(6x+7)\times (8x+5)[/tex]
[tex]A_1=6x(8x+5)+7(8x+5)[/tex]
[tex]A_1=48x^2+30x+56x+35[/tex]
[tex]A_1=48x^2+86x+35[/tex]
The dimensions of mural are (x+4) and (2x+5). So, the area of mural is
[tex]A_2=(x+4)\times (2x+5)[/tex]
[tex]A_2=x(2x+5)+4(2x+5)[/tex]
[tex]A_2=2x^2+5x+8x+20[/tex]
[tex]A_2=2x^2+13x+20[/tex]
The area of remaining wall after the mural has been painted is
[tex]A=A_1-A_2[/tex]
[tex]A=48x^2+86x+35-(2x^2+13x+20)[/tex]
[tex]A=48x^2+86x+35-2x^2-13x-20[/tex]
[tex]A=46x^2+73x+15[/tex]
Therefore area of remaining wall after the mural has been painted is [tex]46x^2+73x+15[/tex] square units.
