Answer:
B=19
C=42
D=119
Step-by-step explanation:
First, fine the value of x, than use that in each angle to find the measurement.
All angles together in the triangle equal 180
Set your formula up as
180=(x+2)+(3x-9)+7x
180=x+3x+7x+2-9
180-2+9=11x
187=11x
187/11=x
17=x
Angle B
B=x+2
B=17+2
B=19
Angle C
C=3x-9
C=3*17-9
C=42
Angle D
D=7x
D=7*17
D=119
Now add all 3 tougher to check your work
19+42+119 = 180
