The length of a rectangle is 3 cm greater than its width. The perimeter is 24 cm. Find the dimensions of the rectangle.

The width is 4.5, and the length is 7.5.

Step-by-step explanation:

We know that the perimeter is 24 cm, and the length is 3 cm greater than the width. We know that the perimeter = l*w. This info gives us an equation:

24 = (x + 3) * 2 + x * 2. The 24 is the perimeter, and x is the width, so l is x + 3. Now we just have to solve for x.

24 = (x + 3) * 2 + x * 2 | Simplify the Parenthesis

24 = 2x + 6 + x * 2 | Subtract 6 from both sides

18 = 2x + x * 2 | x * 2 is 2x

18 = 2x + 2x | 2x + 2x = 4x

18 = 4x | Now we divide by 4

4.5 = x. This mean the width is 4.5, and the length is 4.5 + 3, or 7.5. We can plug these into the original formula to confirm.

24 = 7.5*2 + 4.5*2, 24 = 15 + 9, 24 = 24.