Answer:
First you need to put the variable, x, in a fraction

In this case, 10, is a positive integer, so because its a whole number, we put it with 15 on the other side of the equal sign. Then the +10 will become -10.

Then its easier to calculate, 15 - 10 is 5.

After that you put 5 over 1 and crisscross the equation.

x times 1 is x itself, and 3 times 5 is 15

So in the end x = 15
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