How do you find the inverse of #f(x) =( -2x)/(-7-x)#?

1 Answer
Oct 23, 2015

#f^-1 (x)= (-7x)/(-2-x)#

Explanation:

First, change the term #f(x)# to #y#

Then, switch the x and y values. You should get
#x=(-2y)/(-7-y)#

Next solve for Y
-multiply x on the left side by #(-7-y)# to get rid of the denominator, you should get
#-7x-yx=-2y#

  • add #yx# to both sides in order to get all the Ys on the same side
    -#7x=-2y+yx#

  • factor out the y value from the right side
    -#7x=y(-2+x)#

  • divide both sides by #(-2+x)#
    #(-7x)/(-2-x)=y#

Lastly change the term #y# to #f^-1 (x)# [f inverse of x]
#f^-1 (x)= (-7x)/(-2-x)#