What two numbers add to negative 9 but multiply to 24

There aren't any numbers that add to 24 but multiply to 9. But you can still factorise - remember, you only need to get numbers that add up to the middle number if the coefficient of y^2 is 1. That means if you just have y^2, not 2y^2 or 3y^2 or 16y^2 like we do here. 

16y^2+24y+9 = (4y+3)^2

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 !