The vertex of this parabola is at (-5, -2). When the x-value is -4, the

y value is 2. What is the coefficient of the squared expression in the

parabola’s equation?

(-5,-2)

© A. 1

O B. -1

C. 5

D. 4

y value is 2. What is the coefficient of the squared expression in the

parabola’s equation?

(-5,-2)

© A. 1

O B. -1

C. 5

D. 4

Answer: D. 4

So you know the vertex is at (-5,-2) and there is a point (-4,2). This means you can write it in vertex form.

Vertex form is y= a(x-h)^2 +k

Therefore:

y= a(x+5)^2 -2

Now since you know that plug in the point to find a.

2 = a(-4+5)^2-2

4 = a

So your equation is:

y= 4(x+5)^2 -2

Now you want to know the coefficient of the squared expression. So let’s multiply it out.

y= 4 [(x+5)(x+5)]-2

y= 4(x^2+10x+25)-2

y= 4x^2+40x+100-2

y= 4x^2 + 40x + 98

Therefore your coefficient is 4.