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 \(45\ units\)
