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3 years ago

- A rectangle has a width of 4.2 m and an area of 37.8 m2. Find the length and the

Mathematics

1 answer:

eimsori [14]3 years ago

4 0

Answer: option c

length = 9m

Perimeter = 26.4m

Step-by-step explanation:

A rectangle has a width of 4.2 m and an area of 37.8 m^2

We want yo determine the length of the rectangle and the perimeter of the rectangle.

The perimeter of the rectangle is the distance round the shape. Let the width of the triangle be w.

The perimeter of the rectangle would be expressed as Length + width + length + width. This becomes

2(length +width). So the perimeter of the given rectangle is

2(length + 4.2) but the area is given as 37.8 m^2. Area of a rectangle is length × width. It becomes

37.8= length × 4.2

Length = 37.8/4.2 = 9m

Therefore, the perimeter is

2(length + 4.2) = 2(9+4.2)

Perimeter = 2× 13.2 = 26.4m

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