Question

The perimeter of the rectangle is 146 units. What is the length of the longer side?

Answer 1

we know that

the perimeter of the rectangle is equal to

$P=2W+2L$

where

P is the perimeter of the rectangle

W is the width of the rectangle

L s the length of the rectangle

In this problem

$P=146\ units \\ W=2x\\ L=3x+3$

Substitute the values in the formula above

$P=2W+2L\\ 146=2*(2x)+2*(3x+3)\\ 73=2x+3x+3\\ 5x=70\\ x=14\ units$

$W=2x=2*14=28\ units\\ L=3x+3=3*14+3=45\ units$

therefore

the answer is

the length of the longer side of the rectangle is equal to $45\ units$

Answer 2

2x+2x+3x+3+3x+3=146
10x+6=146
10x=140
x=14
45 units is the longest side