find b and c so that y=2x^2+bx+c has a vertex (1,8)

Question

find b and c so that y=2x^2+bx+c has a vertex (1,8)

Answer 1

The x-value of the vertex for a quadratic is x=-b/(2a)

y = ax²+bx+c

for y =2x²+bx+c, a = 2

At the vertex of (1,8)

1=-b/(2(2))=b/4

b=-4

For (1,8)

8 = 2(1)²-4(1)+c

8=2-4+c

c=10