The graph of the function f(x) = ax^2 + bx + c has a vertex at x = 1 and passes through the points (0, 1) and (-1, -8). Find a, b and c.
to calculate 3 values you need 3 equations. You know that the x-value of the vertex is . So you have:
The coordinates of the given points must satisfy the equation of the function. Plug in the coordinates:
Solve for a, b and c. Use the method which is the most convenient for you. I've got:
a = -3, b = 6 and c = 1