Don L. answered 03/14/16
Tutor
5
(18)
Fifteen years teaching and tutoring basic math skills and algebra
Hi Alex, with this problem there is a "trick" you can use to make it simpler.
The original equation:
x - 6 / (2 - x) = 3x / (x - 2)
You need to clear the fractions in order to solve the equation. If you look at the two fractions, the denominators are almost the same with one denominator being 2 - x and the other being x - 2.
If we multiply the first fraction by -1, we get: + 6 / (x - 2), which gives us the same denominator as the second fraction. We have not changed anything by doing this, but we get the same denominator for both fractions.
Modified equation:
x + 6 / (x - 2) = 3x / (x - 2)
Multiply all terms by x - 2 to clear fractions:
x * (x - 2) + 6 = 3x, note the denominators cancel out.
Clear parenthesis:
x2 - 2x + 6 = 3x
Subtract 3x from both sides:
x2 - 5x + 6 = 0
Factor:
(x -2) * (x - 3) = 0
Solve for x:
x - 2 = 0
x = 2
x - 3 = 0
x = 3
Solution:
x = 2, and x = 3
Questions?

Andrew M.
03/15/16