Plz guysl need an answer plz guys

w = 5

Step-by-step explanation:

The whole perimeter is 400 cm

15 + 15 = 30

40 - 30 = 10

10 divided by 2 = 5

Width = 5 cm

Step-by-step explanation:

The total perimeter is 40 cm. The perimeter is all of the side lengths added together, so the formula is: length + length + width + width = perimeter. We already know that the length is 15 cm and the perimeter is 40 cm, so the equation is: 15 + 15 + width + width = 40. Add 15 + 15 to get the new equation: 30 + width + width = 40. Subtract 30 from both sides now to get: width + width = 10. The two widths, need to be the same number, so we need to find out what double pair makes 10. This lucky number is 5. So the width is 5.

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