A Variable expense is a type of expense that may vary from month to month. This type of expense includes things like electricity, groceries, clothing, and gas. When it comes to the groceries, it is considered to be a variable expense only if the household need the items that are purchased.
All you have to do is combine like terms here...all the x's and then all the constants. 2.3x + 2x -.2x = 4.1x; 14 + 15 = 29, so the perimeter is 4.1x + 29, A above.
