Question 151272
substituting (0,0) __ (0)=a(0)^2+b(0)+c __ 0=c


substituting (-4,-36) __ (-36)=a(-4)^2+b(-4) __ -36=16a-4b


substituting (2,-18) __ (-18)=a(2)^2+b(2) __ -18=4a+2b __ multiplying by 2 __ -36=8a+4b


adding equations __ -36+(-36)=16a-4b+8a+4b __ -72=24a __ dividing by 24 __ -3=a


substituting __ -18=4(-3)+2b __ adding 12 __ -6=2b __ dividing by 2 __ -3=b


Y=-3x^2-3x