Why is angle 1 congruent with angle C in the diagram A. They interior angles to the triangle
B. They are corresponding angles
C. They are exterior angels to the triangle
D. They are vertical angles

Please help me with this answer

They are vertical angles

Step-by-step explanation:

They are opposite each other

c

step-by-step explanation:

c

c.

step-by-step explanation:

because first you have to add the 4x, 9x, and the 7x together and you get 20x and then you add the last numbers up and you get 5and then you put the subtraction sign in there and that's how you get the answer.