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Answer: 4 inches x 7 inches

Step-by-step explanation: Knowing that the formula for the area is length times width, 4 x 7 = 28 square inches. The perimeter of the rectangle with 2 sides that are 4 inches and 2 sides that are 7 inches is 22 inches. (2 x 4) + (2x7) = 8 + 14 = 22 inches.

The dimensions of the note card are length = 4 inches and width = 7 inches or length = 7 inches and width = 4 inches.

Let l be the length of the rectangular note card and w be its width.

Since the area of the rectangular note card is 28 square inches, we have that

lw = 28 (1)(the area of a rectangle).

Also, the perimeter of the rectangular note card is 22 inches. We have that

2(l + w) = 22 (2) (perimeter of a rectangle)

So, l + w = 11 (3)

From (3), l = 11 - w.

Substituting l into (1), we have

(11 - w)w = 28

11w - w² = 28

re-arranging, we have

w² - 11w + 28 = 0

Factorizing, we have

w² - 7w - 4w + 28 = 0

w(w - 7)- 4(w - 7) = 0

(w - 7)(w - 4) = 0

w - 7 = 0 or w - 4 = 0

w = 7 or w = 4

Since l = 11 - w,

substituting w = 7 into l, we have

l = 11 - 7 = 4 inches

substituting w = 4 into l, we have

l = 11 - 4 = 7 inches.

So, we have l = 4 and w =  7 or l = 7 and w = 4

So, the dimensions of the note card are length = 4 inches and width = 7 inches or length = 7 inches and width = 4 inches.

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