Question 766776
y = ax^2+bx+c

(1) (1, -4) -> -4=a+b+c , 
(2) (2, -5) -> -5= 4a+2b+c, 
(3) (3, -10) -> -10=9a+3b+c


(2)-(1):

-5+4=4a-a+2b-b+c-c

-1=3a+b (or 3a+b=-1)

(3)-(1):

-6=8a+2b (or 4a+b=-3)


taking the difference of these 2 we get


4a-3a+b-b=-3+1 (or a=-2)


and thus b=5

Now from (1):
-4=-2+5+c (so c=-7)




y=-2x^2+5x+-7


:)