Problem
The length of a rectangle is \( 3 \mathrm{ft} \) longer than its width. If the perimeter of the rectangle is \( 70 \mathrm{ft} \), find its length and width.
Solution
Step 1 ：Let width be \(w\mathrm{ft}\) and length be \(l\mathrm{ft}\). We are given that \(l = w + 3\mathrm{ft}\).
Step 2 ：Perimeter of the rectangle is given by \(2(w + l) = 70\mathrm{ft}\).
Step 3 ：Substitute the value of \(l\) from step 1 into the equation of step 2: \(2(w + (w + 3)) = 70\).
