The vertical line x=−b2ax = \frac{-b}{2a}x=2a−b is the axis of symmetry of the curve.
y=x2−4x−12y = x^{2} - 4x - 12y=x2−4x−12
Axis of symmetry=x=−(−4)2(1)=42=2\text{Axis of symmetry} = x = \frac{-(-4)}{2(1)} = \frac{4}{2} = 2Axis of symmetry=x=2(1)−(−4)=24=2
