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1. Find the perimeter of the rectangle.

4in w 7in L

O11 in.
O22 in.
O28 in.
O56 in.

User Gbdivers
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2.6k points

1 Answer

1 vote

Answer:

(b) 22 in

Explanation:

You want the perimeter of a rectangle with side lengths 4 inches and 7 inches.

Perimeter

The perimeter of a rectangle is the sum of the lengths of its sides. Your rectangle has two sides that are 4 inches, and two sides that are 7 inches. The perimeter is the sum of these lengths:

P = 4 in + 4 in + 7 in + 7 in

P = 22 in

The perimeter of the rectangle is 22 inches.

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Additional comment

We can save a math operation by recognizing the sum can be arranged to ...

P = (4 in +7 in) +(4 in +7 in) = 2(4 in +7 in)

This is evaluated using one sum and one product, rather than the three sums we need if we simply add the lengths of the four sides.

This is why the usual formula for the perimeter of a rectangle is ...

P = 2(L +W)

User Harshit Satya
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2.9k points