How do you solve the rational equation 5 /( x+4) = 4 + 3/ (x-2)?

1 Answer
Jan 31, 2016

You must put everything on the same denominator and then solve the resulting quadratic equation.

Explanation:

The Least Common Denominator (LCM) would be (x + 4)(x - 2)

(5(x - 2)) / ((x + 4)(x - 2)) = (4(x + 4)(x - 2))/((x + 4)(x - 2)) + (3(x + 4))/((x - 2)(x + 4))

5x - 10 = 4(x^2 + 4x - 2x - 8) + 3x + 12

5x - 10 = 4x^2 + 8x - 32 + 3x + 12

0 = 4x^2 + 6x - 10

0 = 2(2x^2 + 3x - 5)

0 = 2(2x^2 + 5x - 2x - 5)

0 = 2(x(2x + 5) - (1(2x + 5))

0 = 2(x - 1)(2x + 5)

x = 1 and -5/2

Your solution set is x = 1 and -5/2