How do you solve and write the following in interval notation: #abs(2x+5)>=3#?

1 Answer
Jul 14, 2016

(-inf., -4] and [-1, inf.)

Explanation:

I2x + 5I #>=# 3.

Separate solving into 2 parts:
a. #(2x + 5) >= 3#
#2x >= - 2 #
#x >= - 1#

b. #- (2x + 5) >- 3#
#- 2x - 5 >= 3#
#- 2x >= 8#
#x <= -4#
Answers by half closed intervals: (-inf., -4] and [-1, inf.)
Graph

=============== -4 -------------- -1 === 0 ===============