algebra
posted by Anonymous .
Why does the inequality sign change when both sides are multiplied or divided by a negative number? Does this happen with equations? Why or why not? Write an inequality for your classmates to solve. In your inequality, use both the multiplication and addition properties of inequalities.

by multiplying/dividing by a negative number, you are distributing that negative to every part of the equation, making everything effected by the negative opposite. In order to make an inequality sign opposite, you must flip it. with equations you still must multiply/divide everything by the negative, but you can not change an = they are not affected.
3x+18>21 
x<1