1)
f(x)=5x^2-3x+19
a=5, b=-3, c=19
2)
f(x)=x^2-x
a=1, b=-1, c=0
3)
f(x)=-2x^2+5
a=-2, b=0, c=5
4)
f(x)=(x-2)^2 =x^2-4x+4
a=1, b=-4, c=4
1)
f(x)=5x^2-3x+19
a=5, b=-3, c=19
2)
f(x)=x^2-x
a=1, b=-1, c=0
3)
f(x)=-2x^2+5
a=-2, b=0, c=5
4)
f(x)=(x-2)^2 =x^2-4x+4
a=1, b=-4, c=4