When variables are touching, that means after plugging them in, we multiply. So the equation becomes 13 + axb Lets fill a and b in: 13+(2.5)(3) In the order of operations (or PEMDAS),we must multiply first. 2.5 x 3 =7.5 Then the equation becomes: 13 + 7.5 No you just add to get your answer which is (B)20.5 Hope this helps!