How do you graph $| 7 x | \geq 21$ $|7x| \ge 21$ ?

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Answer 1 · 2018-05-31T06:52:14

Please refer to the explanation below.

Firstly, simplify the expression.
So we have,

$| 7 x | \geq 21$ $|7x|>=21$

$\Rightarrow | x | \geq 3$ $=> |x|>=3$ (Dividing both side by 7)

$\Rightarrow x \geq 3 or x \leq - 3$ $=> x>=3 or x<=-3$ (Property of modulus)

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

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

You will get your requird graph.

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How do you graph |7x|≥21|7x| \ge 21?