How do you solve and write the following in interval notation: #-y<-8#?

2 Answers
Jul 2, 2017

Answer:

See a solution process below:

Explanation:

First, multiply each side of the inequality by #color(blue)(-1)# to solve for #y# while keeping the inequality balanced. However, because we are multiplying an inequality by a negative term we must reverse the inequality operator:

#color(blue)(-1) xx -y color(red)(>) color(blue)(-1) xx -8#

#y > 8#

Or, in interval notation:

#(8, +oo)#

Jul 2, 2017

Answer:

#(8, oo)#

Explanation:

First, let's isolate for #y#

#-y<-8#

divide by #-1# on both sides

#y color(red)(>) 8#

when you divide/multiply by a negative number, the sign changes

So now our equation is #y > 8#, or #y# is larger that 8. If we graph it, it looks somethi ng liek ths:
graph{y > 8}

We can see that our range is from #8# to #oo#. If we wqant to write that in interval notation, we'd write it like this:
#(8, oo)#
from #8#, to infinity