How do you graph #|7x| \ge 21#?

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Answer 1 · 2018-05-31T06:52:14

Please refer to the explanation below.

Firstly, simplify the expression.
So we have,

#|7x|>=21#

#=> |x|>=3# (Dividing both side by 7)

#=> x>=3 or x<=-3# (Property of modulus)

Since you are going to plot this on 2-D, mark the critical lines, i.e., #x=3 and x=-3#

Now shade all the region on the Right Hand Side of #x=3#
And, region on the Left Hand Side of #x=-3#

You will get your requird graph.

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