How do you solve #\frac { 6} { x + 3} = \frac { 9x } { x ^ { 2} - 9}#?

1 Answer
Jul 22, 2017

Use the formula of multiplying polynomials:
#(x+y)(x-y)=x^2-y^2#
and use Least Common Denominator (LCD) to isolate and solve for x.

Explanation:

#6/(x+3)=(9x)/(x^2-9)#

Simplify by making the common denominator between the two fractions.

#(6(x-3))/(x^2-9)=(9x)/(x^2-9)#

You can now get rid of the denominators.

#6(x-3)=9x#

Solve for x.

#-3x=18#
#x=-6#