Question

what is the axis of symmetry of the quadratic function (y = 2(x + 3)^2 + 5)?

(x = -5)
(x = -3)
(x = 5)
(x = 3)

Explanation:

Identify the vertex form parameters

$$ y = a(x - h)^2 + k $$

$$ y = 2(x + 3)^2 + 5 = 2(x - (-3))^2 + 5 $$

$$ h = -3,\quad k = 5 $$

Determine the axis of symmetry

$$ x = h $$

$$ x = -3 $$

Answer:

• \(x = -5\)
• \(x = -3\) (Correct answer)
• \(x = 5\)
• \(x = 3\)