Question

The length of a rectangle is 3 units shorter than one-third of the width, x. Enter an expression in the box that represents the perimeter of the rectangle. Note: Use one variable and a fraction in the answer.

Help please! I have absolutely no idea how to solve!!!! ^^^

Answer 1

Since length is 3 less than 1/3 width, set up equation l=(1/3)w-3. Because P=2(l+w), substitute l with the euation and get P=2(4/3w-3)

Answer 2

Let

y----------> the length side of the rectangle

x-----------> the width side of the rectangle

we know that

the perimeter of the rectangle is equal to

$P=2x+2y$ --------> equation $1$

$y=\frac{x}{3}-3$ --------> equation $2$

substitute equation $2$ in equation $1$

$P=2x+2[\frac{x}{3}-3]\\ \\P=2x+ \frac{2x}{3}-6 \\ \\P=(\frac{8x}{3}-6)\ units$

therefore

the answer is

$P=(\frac{8x}{3}-6)\ units$