When we multiply or divide by a negative number, the INEQUALITY direction SWITCHES

Here is the math lesson for today.

9x > 81


so
9x  > 81
__     __
9        9



x  >  9


BUT WHEN THE Inequality has a NEGATIVE number multiply or dividing the X, then we have to SWITCH DIRECTION.


-9X > 81

-9x  >  81
__       __
-9       - 9


x  <  -9


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