1/2x + 13 = 9
You want to get the variable (x) by itself, so to do that, add or subtract the number with the variable. If it's positive, you subtract, if it is negative, you add.
1/2x + 13 = 9
-13 -13
1/2x = -4
and now you should have that. now, all you need to do, is multiply or divide. If the variable is being multiplied by the number next to it (1/2x) then you divide it on both sides. If it is being divided by the number next to it (1/2 / x) then you multiply it on both sides. In this case, you are dividing it on both sides.
1/2x = -4
/ 1/2 / 1/2
-4 divided by 1/2 equals -2. So X = -2. I hope this helped.
