Question

The length of a rectangle is 4 more than 3 times the width. If the perimeter of the rectangle is 18.4 cm, what is the

area of the rectangle?

Answer 1

let $x$ be the width then $4+3x$ is length. The perimeter is $2(l+b) = 2(x + (4+3x)) = 18.4$. Solve for it, it will get you
$$
2x + 6x + 8 = 18.4 \implies 8x = 18.4 -8 = 10.4
$$
Divide both sides by $8$ and get $x = 10.4/8$. Since you have width, you can find length as $4+3x$ and multiply them to find the area.