2x + 2 dollars, because you're adding x and x + 2
It helps to imagine the variable a sort of as a unit. Like with 5 minus 12 lemons, it has no bearings on the addition/subtraction here.
Factor out a and subtract.
The answers are B and D hope this helps.
4x - 2(3x - 9)....distribute the 2 thru the parenthesis
4x - 6x + 18....combine like terms
-2x + 18 <===
The length of the rectangle is 16.