Question

Find the equation of the axis of symmetry of the following parabola using graphing technology.
y, equals, x, squared, plus, 6, x, plus, 17
y=x
2
+6x+17

Answer 1

The axis of symmetry is x = -b/(2a). For y = x^2 + 6x + 17, a = 1 and b = 6, so

x = -6/(2·1) = -3.

(Completing the square: y = (x+3)^2 + 8, vertex at (-3, 8), so axis x = -3.)