The width of a rectangle is 2/5 its length. Find the dimensions if the perimeter is 42 meters.length = 13m, Width = 8m.not enough information.length = 15m, Width = 6m.length =1 11m, Width = 10m.

Accepted Solution

The formula to find the perimeter of a rectangle is P= 2(l+w). Substitute what we know in to the equation:

•42=2(l+(2/5l)). We can have width represented at (2/5l) because it’s 2/5 of the length. Now add them together to get a single coefficient for l.
•42= 2(7/5l). Multiply 7/5 by 2.
•42= (14/5l). Multiply both sides by the reciprocal of 14/5, which is 5/14, to get l by itself.
•l= 15.

Now that we know the value of l, we know that the length is 15m. To find the width, we multiply 15 by 2/5, which is 6. Therefore, the third option is correct because the length is 15m and the width is 6m.