How do you solve (2x)/ (x+2) - 2 = (x-8) / (x-2)?

2 Answers
Jun 10, 2015

I would find a common denominator and then solve for x.

Explanation:

Have a look:
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Jun 10, 2015

Multiply through by (x+2) and (x-2), expand and simplify to get:
0 = x^2-2x-24 = (x-6)(x+4), hence x = 6 or x=-4

Explanation:

Given:

(2x)/(x+2)-2 = (x-8)/x-2

Multiply both sides by (x+2)(x-2) to get:

2x(x-2)-2(x+2)(x-2) = (x-8)(x+2)

Note that when we multiply by (x+2)(x-2) we could in theory introduce spurious extra solutions x=+-2, but these are excluded values of the original equation anyway.

Multiplying out:

cancel(2x^2)-4x-cancel(2x^2)+8 = x^2-6x-16

Add 4x-8 to both sides to get:

0 = x^2-2x-24 = (x-6)(x+4)

To get this factorization, I looked for a pair of factors of 24 whose difference is -2, since:

(x - a)(x + b) = x^2-(a-b)x-(axxb)

Since (x-6)(x+4) = 0, the solutions are x=-4 and x=6.