How do you decide whether the relation #abs(x)-y=5# defines a function?

1 Answer
Jul 9, 2017

As #x# is the independent variable and any 1 value of #x# gives only 1 answer for #y# this is a function

This is called a one-to-one mapping

Explanation:

Make #x# the independent variable and #y# the dependent (the answer)

Add #y# to both sides

#|x|=5+y#

Subtract 5 from both sides

#y=|x|-5#

As #x# is the independent variable and any 1 value of #x# gives only 1 answer for #y# this is a function

This is called a one-to-one mapping

Tony B