Question 213158
f(x)=ax^2+bx+c
for x=0
f(0)=c  as given f(0)=6 so c=6
for x=-1
f(-1)=a-b+6  as given f(-1)=15 so a-b+6=15; a-b=9 _____e
for x=1
f(1)=a+b+6 as given f(1)=1 so a+b+6=1; a+b=-5 _____f
by adding eq e & f  we have a=2
and put value of 'a' in eq f we have b=-7 so we have
a=2;b=-7;c=6