Answer:
m<a=139°
m<b=23°
m<c=18°
Explanation:
interior angles of a triangle =180°
40x -21+31-2x+x+14=180
39x+24=180
39x=180-24.
39x=156
39x/39=156/39
x=4.
m<a= (40x-21)
= (40(4)- 21)
=(160-21)
=139°
m<b =(31-2x)
=(31- 2(4))
= (31-8)
= 23°
m<c=(x+14)
= (4+14)
=18°