20/x-19 + -6/x-18 = 0 Ok, I'm assuming what you have written doesn't have any parentheses, else if it's supposed to be 20/(x-19), the result will change.
First step is to get x on one side of the equals sign, so just add 19 and 18 to both sides... or think of it as moving those numbers to the other side of the equals sign and changing their sign.
20/x + -6/x = 19 + 18
20/x + -6/x = 37
Now, multiply both sides by x. (x/x = 1)
20 + -6 = 37x
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