Answer:
d) 76
Step-by-step explanation:
there are 180 degrees inside a triangle
so, 40+(3x+10)+(2x+20) = 180
combine 'like terms' to get:
5x + 70 = 180
subtract 70 from each side to get:
5x = 110
divide each side by 5:
x = 22
m∠BCA = 3(22)+10
= 66+10
= 76°
