How do you solve for x in #x=18/(x+3)#?

2 Answers
Jun 23, 2016

Answer:

# x=-6, x=3.#

Explanation:

#x=18/(x+3)#
# rArr x(x+3)=18.#
# rArr x^2+3x-18=0.#
# rArr x^2+6x-3x-18=0,.........[6xx3=18, 6-3=3.]#
# rArr x(x+6)-3(x+6)=0.#
# rArr (x+6)(x-3)=0.#
# rArr x=-6, x=3.#

Clearly, these satisfy the given eqn. hence, the roots are confirmed.

Jun 23, 2016

Answer:

So solutions are #x=3" and "x=-6#

Explanation:

Multiply both sides by #(x+3)#

#x(x+3)=18xx(x+3)/(x+3)#

But #(x+3)/(x+3)=1# giving;

#x(x+3)=18#

Subtract #18# from both sides

#x(x+3)-18=18-18#

#x(x+3)-18=0#

Expand the brackets

#x^2+3x-18=0 larr" solve as a quadratic"#
'~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Note that #(-3)xx6=-18# and that #-3+6=+3#

#=>(x-3)(x+6)=0#

So solutions are #x=3" and "x=-6#