Question 238293
When we have an inequality or equality, we need to isolate the variable in order to find its value.  
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When we add or sustract from both sides of the inequality, the inequality symbol remains the same.
However, when we multiply or divide a NEGATIVE value on both sides, the inequality symbol changes direction.
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It also changes direction if we decide to swap one side for the other.
Here are a few examples:
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Sum operation:
{{{20>-2+k}}}
{{{20+2>k}}}
{{{22>k}}} 
If you decide to swap sides, then you'd say: {{{k<22}}} to maintain the same result.
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Negative Multiplication operation:
{{{30>-(p/4)}}}
{{{30*(-4)<p}}}
{{{-120<p}}} ...same as to say... {{{p>-120}}}
Positive Multiplication operation:
{{{30>p/4}}}
{{{30*4>p}}}
{{{120>p}}} ...same as to say... {{{p<120}}}
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Now, let's work on your problem:
{{{-0.4x<-36}}}
In this case, we need to divide by -0.4, so we know the inequality symbol changes direction... and... negative divided by negative yields a positive answer.
{{{x>(-36)/-0.4}}}
{{{x>90}}}
Done!