Answer :
Given:
The one side of a rectangle is, a = 2x.
The second sides of a rectangle is, b = x + 3.
The objective is to find the perimeter of the rectangle.
Explanation:
The general formula of perimeter of rectangle is sum of all four sides.
[tex]\begin{gathered} P=a+b+a+b \\ P=2a+2b \\ P=2(a+b)\text{ . . . . . . . (1)} \end{gathered}[/tex]To find expression:
Now, substitute the given values in the equation (1).
[tex]\begin{gathered} P=2(2x+(x+3)) \\ =2(3x+3) \\ =6x+6 \end{gathered}[/tex]Hence, the expression for perimeter of the rectangle is P = 6x + 6.