Answer:
yes, it is a function
D: {-4, -3, 0, 4}
R: {2, 4}
Step-by-step explanation:
Yeah I'm not sure but I think it's 6
The answer would be A, complementary angles must add up to 90 degrees
Answer : B
the distance between the points (4,3) and (2,-1)
We apply distance formula

(x1,y1) is (4,3)
(x2,y2) is (2,1)


d^2 = 4+16 = 20
Take square root on both sides
So 
the distance between the points (4,3) and (2,-1) is 2sqrt(5)