How do you evaluate #-22< - 23h - 54< - 15#?

1 Answer
Nov 13, 2017

See a solution process below:

Explanation:

First, add #color(red)(54)# to each segment of the system of inequalities to isolate the #h# term while keeping the system balanced:

#-22 + color(red)(54) < -23h - 54 + color(red)(54) < -15 + color(red)(54)#

#32 < -23h - 0 < 39#

#32 < -23h < 39#

Next, divide each segment by #color(blue)(-23)# to solve for #h# while keeping the system balanced. However, because we are multiplying or dividing inequalities by a negative number we must reverse the inequality operators:

#32/color(blue)(-23) color(red)(>) (-23h)/color(blue)(-23) color(red)(>) 39/color(blue)(-23)#

#32/-23 color(red)(>) (color(blue)(cancel(color(black)(-23)))h)/cancel(color(blue)(-23)) color(red)(>) 39/-23#

#-32/23 color(red)(>) h color(red)(>) -39/23#

Or

#h > -39/23# and #h < -32/23#

Or, in interval notation:

#(-39/23, -32/23)#