Angle x is angle x is (2n + 12) and angle y is. 3(n+18 find the measure of angle x

Zroms according to the synthetic division below, which of the following statements are true? check all that apply. 352 -2 6 -12 12 2 4 0 i a. (x-3) is a factor of 2x2 - 2x - 12. b. the number 3 is a root of f(x) = 2x2 - 2x - 12. c. (2x2 - 2x - 12) = (x + 3) = (2x + 4) d. (2x2 - 2x-12) - (x-3) = (2x + 4) e. (x+3) is a factor of 2x2 - 2x - 12. o f. the number -3 is a root of fx) = 2x2 - 2x - 12. previous

Can someone me out here number 4 plz

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.