How do you evaluate #|3k - 2| < 4#?

1 Answer
Sep 14, 2017

See a solution process below:

Explanation:

The absolute value function takes any term and transforms it to its non-negative form. Therefore, we must solve the term within the absolute value function for both its negative and positive equivalent.

#-4 < 3k - 2 < 4#

First, add #color(red)(2)# to each segment of the of the system of inequalities to isolate the #k# term while keeping the system balanced:

#-4 + color(red)(2) < 3k - 2 + color(red)(2) < 4 + color(red)(2)#

#-2 < 3k - 0 < 6#

#-2 < 3k < 6#

Next, divide each segment by #color(red)(3)# to solve for #k# while keeping the system balanced:

#-2/color(red)(3) < (3k)/color(red)(3) < 6/color(red)(3)#

#-2/3 < (color(red)(cancel(color(black)(3)))k)/cancel(color(red)(3)) < 2#

#-2/3 < k < 2#

Or

#k > -2/3# and #k < 2#

Or, in interval notation:

#(-2/3, 2)#