Factor completely.
6x²+ 3x - 63
a. 3(2x + 7)(x - 3)
b. (3x + 9)(2x - 7)
c. (6x + 21)(x - 3)
d. 3(2x²+ x - 21)

It would be A. work the equation backwards. 3(2x+7)(x-3)    * represents multiply
3*2x=6x
3*7=21          leaves you with (6x+21)(x-3)
follow FOIL: first outer inner last
F:6x*x=6x²
O:6x*-3=-18x
I:21*x=21x
L:21*-3=-63
6x²    -18x+21x=3x    -63
you would get 6x²+3x-63 so A is the answer

This polygon has 4 sides
180(4-2) = 180(2) = 360 degree
80+90+2x + 3x = 360
170+5x = 360
5x = 190
x= 38
measure of angle t is 2(38)= 76
the answer is c. trust me
hope this !