6 viewed last edited 4 years ago
How do I know when to change the inequality symbol to the other direction when solving?
Mahesh Godavarti

Only when you are multiplying or dividing both sides by a negative number. Otherwise, you don't change the direction of the inequality.

Note that if you rewrite x \lt y to have y on the left and x on the right then you will have to switch the inequality sign.

Note that the pointy end is always pointing at the smaller quantity.

Therefore, x \lt y is the same as y \gt x .

This is a key fact to remember.