(12x -2) - (-3x + 4) anyone got the answer?

How many sides does a regular polygon have if each exterior angle measure is 45 degrees explain your answer, i really don't understand this.

An expression for the average of x 2x and 3y

Which law states that if a conditional is true and its hypothesis is true, then the conclusion is true? a. the law of syllogism c. the law of detachment b. the law of conditional d. the law of deductive reasoning