Answer:
1)
2A)
2B)
Explanation:
1)
First, let's write the expressions for the area of the entire shaded region and the white area.
The formula for the area of a rectangle is given by:
For the entire shaded rectangle, the length is (4x) and the width is (x+2). So, the area is:
For the white rectangle, the length is (3x+5) and the width is (x). So, the area is:
The shaded area is the entire shaded rectangle minus the area of the white rectangle. Therefore, our expression would be:
2)
Part A)
So, we are given that the length of the rectangle is 3 inches greater than the width.
The area of a rectangle is given by:
So, let w be width and let l be the length.
Since the length is 3 inches greater than the width, this means that the l is (w+3).
Thus, substitute. Our expression will therefore be:
Since we want a polynomial, let's expand:
Part B)
To find the area when the width is 4, substitute 4 for w:
Square and multiply:
Add:
So the area is 28 square inches.