Question

Complete the statements below that show y = x2 + 2x - 1 being converted to vertex form

Answer 1

Answer:

$y=(x+1)^2-2$

Step-by-step explanation:

General polynomial formula of a quadratic equation

$ax^2+bx+c$

Equation $y= x^2+2x-1$

$a= 1\\ b=2\\ c=-1$

The formula to find the x coordinate of the vertex is

$V_{x}= \frac{-b}{2a}$

$V_{x}=\frac{-2}{2(1)} \\ V_{x}= -1$

Now to find the y coordinate of the vertex we substitute the found value of the x coordinate in $y= x^2+2x-1$

$y= (-1)^2+2(-1)-1 \\ y= 1-2-1\\ y=-2$

The general vertex formula for any quadratic function is

$y= a(x-x_{v})^2+y_{v}$

Replace

$y= 1(x-(-1))^2+(-2)\\ y=(x+1)^2-2$

Answer 2

Vertex form should be : y = (x+1)^2 - 2, where the vertex is (-1,-2)