9
advanced-math

Find the vertex of y=x2+6xy = x^2 + 6x.

A

(−3,−9)(-3, -9)

B

(3,27)(3, 27)

C

(−3,9)(-3, 9)

D

(0,0)(0, 0)

Correct Answer: A

Choice A is the correct answer.

  1. x=−b/2a=−6/2=−3x = -b/2a = -6/2 = -3.
  2. y=(−3)2+6(−3)=9−18=−9y = (-3)^2 + 6(-3) = 9 - 18 = -9.
  3. Vertex is (−3,−9)(-3, -9).

Choice B is incorrect because of sign error on x. Choice C is incorrect because of sign error on y. Choice D is incorrect.

Next
Question 10 →
Back to Set
Set 10: Quadratic Equations and Functions 10