Set 8: Quadratic Equations

Explanation

Answer: A

Which equation has an axis of symmetry at $x = 3$ ?

$y = x^2 - 6x + 5$

✓ Correct

$y = x^2 + 6x + 5$

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

$y = 2x^2 - 6x + 5$

Detailed Explanation

Choice A is correct. Choice A is the correct answer. We check $x = -b/2 a$ for each option. * A: $-(-6) / 2(1) = 6/2 = 3$ . (Correct) * B: $-6 / 2(1) = -3$ . * C: $-(-3) / 2(1) = 1.5$ . * D: $-(-6) / 2(2) = 6/4 = 1.5$ . Choice B is incorrect because axis is $x=-3$ . Choice C is incorrect because axis is $x=1.5$ . Choice D is incorrect because axis is $x=1.5$ .

Key Steps:

•

The correct answer is $y = x^2 - 6x + 5$

Why others are wrong:

B: Choice B is incorrect and may result from a calculation error.

C: Choice C is incorrect and may result from a calculation error.

D: Choice D is incorrect and may result from a calculation error.

← Previous Next →

🎯 Keep Practicing!

Master all sections for your best SAT score

📚Reading & Writing→📖Vocabulary→