How do you solve #-2\leq \frac { 2x - 1} { 4} < 2#?

1 Answer
Jan 15, 2018

See a solution process below:

Explanation:

First, multiply each segment of the system of inequalities by #color(red)(4)# to eliminate the fraction while keeping the system balanced:

#color(red)(4) xx -2 <= color(red)(4) xx (2x - 1)/4 < color(red)(4) xx 2#

#-8 <= cancel(color(red)(4)) xx (2x - 1)/color(red)(cancel(color(black)(4))) < 8#

#-8 <= 2x - 1 < 8#

Next, add #color(red)(1)# to each segment to isolate the #x# term while keeping the system balanced:

#-8 + color(red)(1) <= 2x - 1 + color(red)(1) < 8 + color(red)(1)#

#-7 <= 2x - 0 < 9#

#-7 <= 2x < 9#

Now, divide each segment by #color(red)(2)# to solve for #x# while keeping the system balanced:

#-7/color(red)(2) <= (2x)/color(red)(2) < 9/color(red)(2)#

#-7/2 <= (color(red)(cancel(color(black)(2)))x)/cancel(color(red)(2)) < 9/2#

#-7/2 <= x < 9/2#

Or

#x >= -7/2#; #x < 9/2#

Or, in interval notation:

#[-7/2, 9/2)#