Help please it’s due at 11:59 I’m begging please I am so confused

To solve the system of equations below, grace isolated the variable y in the first equation and then substituted into the second equation. what was the resulting equation? 3y=12x x^2/4+y^2/9=1

Which ordered pair identifies a point in quadrant iv? a) (2, 5) b) (0, 1) c) (-1, -1) d) (12, -5) which quadrant is (-4,-6) in? a) i. b) ii. c) iii. d) iv.

Ineed with question three. i don't understand how i'm supposed to achieve 3 marks.