Make x the subject of the equation, y = [(x+4) / (x-3)] - 6 Please help?

2 Answers
Feb 17, 2018

#x=(3y+22)/(y-7)#

Explanation:

Given:
#y=(x+4)/(x-3)-6#
Multiplying throughout by #x-3#

#y(x-3)=x+4-6(x-3)#

#xy-3y=x+4+6x+18#
#xy-3y=7x+22#

#xy-7x=22+3y#
#x(y-7)=22+3y#

#x=(22+3y)/(y-7)#

Rearranging

#x=(3y+22)/(y-7)#

Feb 17, 2018

#x=(3y+22)/(y+5)#

Explanation:

#y=(x+4)/(x-3)-6#

#"add 6 to both sides"#

#rArry+6=(x+4)/(x-3)larrcolor(blue)"cross multiply"#

#(y+6)(x-3)=x+4larrcolor(blue)"expand factors on left"#

#xy-3y+6x-18=x+4#

#"collect terms in x on the left"#

#xy+6x-x=4+18+3y#

#rArrxy+5x=22+3y#

#"take out a "color(blue)"common factor of x"#

#x(y+5)=22+3y#

#"divide both sides by "(y+5)#

#rArrx=(3y+22)/(y+5)#