SOLUTION: I don't understand the inverse operations when fractions are involved the problem I am working on is: x/12 +8=105 I started: 105-8 = 97, but I don't know the next step s

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Question 236179: I don't understand the inverse operations when fractions are involved
the problem I am working on is:
x/12 +8=105
I started: 105-8 = 97,
but I don't know the next step should I multiply or divide by 12?
thanks for your help,
Katie
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
When you say x%2F12=97, you're saying: "some number divided by 12 equals 97"

In order to isolate 'x', you need to "undo" every operation that is being done on 'x'. So in this case, you need to undo that division (note: in the first step, you undid the addition of 8 by subtracting 8 from both sides). Since the opposite of division is multiplication, this means you need to multiply both sides by 12 like so:

cross%2812%29%28x%2Fcross%2812%29%29=97%2A12

and simplify

x=1164


So the solution is x=1164