Answer:
(43[tex]x^{2}[/tex] - 26x) [tex]ft^{2}[/tex]
Step-by-step explanation:
Area of the yard that is not pat of the sandbox = Area of the yard - Area of the sandbox
Since both the yard and the sandbox has a rectangular shape, then;
Area of a rectangle = length x width
So that,
Area of the yard = length x width
= (6x+7) x 8x
= (48[tex]x^{2}[/tex] + 56x) [tex]ft^{2}[/tex]
Area of the sandbox = length x width
= (x+6) x 5x
= (5[tex]x^{2}[/tex] + 30x) [tex]ft^{2}[/tex]
Thus,
Area of the yard that is not pat of the sandbox = (48[tex]x^{2}[/tex] + 56x) - (5[tex]x^{2}[/tex] + 30x)
= 48[tex]x^{2}[/tex] + 56x - 5[tex]x^{2}[/tex] - 30x
= (43[tex]x^{2}[/tex] - 26x) [tex]ft^{2}[/tex]
Area of the yard that is not pat of the sandbox is (43[tex]x^{2}[/tex] - 26x) [tex]ft^{2}[/tex].