What is the least common denominator for #\frac{2x}{x-4}+\frac{x}{4-x}#? Algebra Rational Equations and Functions Addition and Subtraction of Rational Expressions 1 Answer YouDid Dec 18, 2014 #x-4#. When you multiply the second fraction with #-1#, you get #(2x)/(x-4)+(-x)/-(4-x) = (2x)/(x-4)+(-x)/(x-4) = x/(x-4)# Answer link Related questions What is Addition and Subtraction of Rational Expressions? How do you add or subtract rational expressions with the same denominator? How do you add or subtract rational expressions with unlike denominator? How do you find the least common denominator for rational expressions? How do you simplify #\frac{2}{x+2}-\frac{3}{2x-5}#? How do you add #\frac{5}{2x+3}+\frac{3}{2x+3}#? How do you add #\frac{3x-2}{x-2}+\frac{1}{x^2-4x+4}#? How do you subtract #\frac{2x}{x^2+10x+25}-\frac{3x}{2x^2+7x-15}#? How do you add #3/(2x-4)+x/(x+2)#? How do I simplify this rational expression #5/(6x^3) + x/(x^2-12x)#? See all questions in Addition and Subtraction of Rational Expressions Impact of this question 6271 views around the world You can reuse this answer Creative Commons License