How can i anwser this one? ?
4x2+16x=0

Divide each side of the equation by 4 :

x² + 4x = 0

Factor the left side:

x (x + 4) = 0

This equation is true if x=0 or if x=-4 , so those are the two solutions.

So the first thing we do is to multiply the top equation by 3. the reason i want to do this is i notice there will be a 6y on both equations and can possibly add/subtract them. so we get 6y = -3x + 27. adding that and the second equation we get 6x = 27-15 which is 12. divide by 6 and we get 2. ∴ x = 2. substituting 2 into the first equation we get 2y = -2 + 9 which is 7. divide by 2 and we get 7/2. ∴ y = 7/2, x = 2.