198k views
3 votes
From the equation, find the axis of symmetry of the parabola.

y = x^2+ 3x + 1

A. X= 3/2
B. Y= 1
C. X=3
D. X= -3/2

User Mig
by
8.2k points

2 Answers

6 votes

Answer:

is D

Explanation:

User Salvador Rueda
by
6.6k points
4 votes

Answer:

D

Explanation:

Quadratic has a general form of:


ax^2 + bx + c = 0

The quadratic given here is:


y = x^2 + 3x + 1

Matching it with the general form, we can see that:

a = 1 [coefficient of x^2]

b = 3

c = 1

Now, if we look at the formula for axis of symmetry, we can easily solve this out. The axis of symmetry is given by:

Axis of Symmetry is
x=-(b)/(2a)

We know a = 1 and b = 3, so we have:


x=-(b)/(2a)\\x=-(3)/(2(1))\\x=-(3)/(2)

Hence,

D is the correct answer.

User Piotr Malec
by
8.1k points