Answer: Linear pair
Step-by-step explanation:
They are a linear pair because
1) their angles add up to be 180 so complementary is out
2) they aren't vertical of each other so vertical angles is out
And 3) they aren't adjacent angles
It is 50 because you have to subtract the area of the triangle (14) from the area of the square (64)
Answer: y=-2x+9
Step-by-step: Subtract 2x from 2x+y=9 and get y=-2x+9