138,070 views
34 votes
34 votes
Put the quadratic into vertex form and state the coordinates of the vertex. y= x² – 2x – 3 Vertex Form: y = Vertex: Submit Answer

Put the quadratic into vertex form and state the coordinates of the vertex. y= x² – 2x-example-1
User Jhogendorn
by
2.0k points

1 Answer

8 votes
8 votes

The Vertex form of a Quadratic equation is:


f(x)=a\mleft(x-h\mright)^2+k

Where the vertex of the parabola is:


(h,k)

Given the following Quadratic equation:


y=x^(2)-2x-3

You can write in Vertex form by completing the square. The steps are:

1. You need divide the coefficient of the x-term by 2, square it and add it to both sides of the equation. Notice that:


((2)/(2))^2=1^2=1

Then:


y+(1)=x^(2)-2x-3+(1)

2. Move the term to the left side:


y+3+(1)=x^2-2x+(1)

3. Simplifying and factoring:


y+4=(x-1)^2

4. Solve for "y":


y=(x-1)^2-4

Now you can identify that:


\begin{gathered} h=1 \\ k=-4 \end{gathered}

The answer is:

a. Vertex form:


y=(x-1)^2-4

b. Vertex:


(1,-4)

User Vivian Miranda
by
2.4k points