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The length of a rectangle is 12cm great her than twice it’s width. If the perimeter of the rectangle is 48 cm, calculate it’s length and width.

User Fuxia
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1 Answer

6 votes

Answer: length = 20cm and width = 4cm✔️

Explanation:

Perimeter of a rectangle = 2length + 2width } Equation 1

Since we know the length is 12cm greater than twice its width:

length = 2width + 12cm } Equation 2

We can substitute this value for length in the equation 1 :

Perimeter = 2(2width + 12cm) + 2width

Perimeter = 4width + 24cm + 2width = 6width + 24cm

Since we know the perimeter is 48cm, we can substitute here :

48cm = 6width + 24cm

6width = 48cm - 24cm = 24cm

width = 24cm/6 = 4cm✔️

Now we can substitute this value in the equation 2

length = 2width + 12cm } Equation 2

length = 2x4cm + 12cm = 8cm + 12cm = 20cm✔️

Answer: length = 20cm and width = 4cm✔️

Checking

Perimeter = 2length + 2width

Perimeter = 2x20cm + 2x4cm = 40cm + 8cm = 48cm✔️ checked!

Spymore

User Mike Graham
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