How do you solve #-2r<(6-2r)/5# and graph the solution on a number line?

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Answer 1 · 2017-03-17T11:20:16

#r > -3/4#

An open circle on #-3/4# and a line drawn to the right.

Treat inequalities in exactly the same way as an equation, but you may not cross-multiply.

If you multiply or divide by a negative value, the inequality sign changes around.

#-2r < (6-2r)/5" "xx 5#

#-2r color(red)(xx5) < ((6-2r)color(red)(xx5))/5#

#-10r < 6-2r" "#re-arrange the terms to make #r# positive

#-6 < -2r +10r#

#-6 <8r" "div 8#

#-6/8 < r#

#r > -3/4#

On the number line this will shown as an open circle on #-3/4# because it is NOT included as part of the solution, and a line drawn to the right.