## Algebra 1: Common Core (15th Edition)

We need to get the x alone. Thus, we cancel out the subtraction by adding 9.1 on both sides. This leaves us with the equation $19.1=.3x$. This is the same as $19.1=3/10x$. In the equation $19.1=3/10x,$ x is being multiplied by a fraction, which we must cancel out. In order to cancel out a fraction being multiplied by a variable, we multiply both sides of the equation by the reciprocal of the fraction, which is the fraction flipped upside down. (For instance, the reciprocal of ⅖ is 5/2). Thus, we multiply both sides of the equation by 10/3 to obtain that x=63 2/3. We plug 63 2/3 in for x and confirm that our answer is, indeed, correct.