Question

Sketch the quadratic function f(x) = x2 + 4x + 3. Which key feature of the graph is given incorrectly?

A) minimum (-2, -1)
B) y-intercept (0, 2)
C) x-intercept (-3, 0)
D) x-intercept (-1, 0)
Hurry if possible

Answer 1

B

Explanation:

Answer 2

Given quadratic function
`f(x)= x^2+4x+3.`

Let us find vertex of the graph first.

x-coordinate of the vertex = -b/2a = -4/2(1) = -4/2 = -2.

y-coordinate of the vertex = (-2)^2+4(-2)+3 = 4-8+3 = -1.

Therefore, vertex is at (-2,-1).

The leading coefficient of quadratic function f(x)= x^2+4x+3 is 1.

And it's a positive number.

So, the parabola open up and it would have a minimum at it's vertex point.

Let us find some more points on the graph :

x=-3

(-3)^2 +4(-3) +3 = 9 -12 +3 =0

x=-1

(-1)^2 +4(-1) +3 = 1 -4 +3 = 0.

From the graph, we can see vertex is at (-2,-1) and x-intercepts at (-1,0), (-3,0) and y-intercept at (0,3).

Therefore, following is the key feature of the graph is given incorrectly:

B) y-intercept (0, 2)