Question 682853
{{{-3<2x+5<=15}}}
Subtract 5 from each segment of the inequality
{{{-3-5<2x+5-5<=15-5}}}
...
{{{-8<2x<=10}}}
Divide each segment of the inequality by 2
{{{-8/2<2x/2<=10/2}}}
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{{{-4<x<=5}}}
...
...
f(x) = -x + 2x
f(-2) = -(-2) + 2(-2)
 = 2 + -4
 = -2
f(-2) = -2
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