Worksheet graphing quadratics from standard form find the vertex axis of symmetry answers

Worksheet graphing quadratics from standard form find the vertex axis of symmetry answers

Here's how it works

Worksheet graphing quadratics from standard form find the vertex axis of symmetry answers

01. Edit your form online

Type text, add images, blackout confidential details, add comments, highlights and more.

Worksheet graphing quadratics from standard form find the vertex axis of symmetry answers

02. Sign it in a few clicks

Draw your signature, type it, upload its image, or use your mobile device as a signature pad.

Worksheet graphing quadratics from standard form find the vertex axis of symmetry answers

03. Share your form with others

Send it via email, link, or fax. You can also download it, export it or print it out.

How to edit worksheet graphing quadratics from standard form answer key with DocHub

Worksheet graphing quadratics from standard form find the vertex axis of symmetry answers

9.5

Ease of Setup

DocHub User Ratings on G2

9.0

Ease of Use

DocHub User Ratings on G2

be ready to get more

Complete this form in 5 minutes or less

Get form

be ready to get more

Complete this form in 5 minutes or less

Get form

A quadratic equation is a polynomial equation of degree 2 .  The standard form of a quadratic equation is

0 = a x 2 + b x + c

where   a , b and c are all real numbers and a ≠ 0 .

If we replace 0 with y , then we get a quadratic function

      y = a x 2 + b x + c

whose graph will be a parabola .

The axis of symmetry of this parabola will be the line x = − b 2 a . The axis of symmetry passes through the vertex, and therefore the x -coordinate of the vertex is − b 2 a . Substitute x = − b 2 a in the equation to find the y -coordinate of the vertex. Substitute few more x -values in the equation to get the corresponding y -values and plot the points. Join them and extend the parabola.

Example 1:

Graph the parabola y = x 2 − 7 x + 2 .

Compare the equation with y = a x 2 + b x + c to find the values of a , b , and c .

Here, a = 1 , b = − 7 and c = 2 .

Use the values of the coefficients to write the equation of axis of symmetry .

The graph of a quadratic equation in the form   y = a x 2 + b x + c has as its axis of symmetry the line x = − b 2 a . So, the equation of the axis of symmetry of the given parabola is x = − ( − 7 ) 2 ( 1 ) or x = 7 2 .

Substitute x = 7 2 in the equation to find the y -coordinate of the vertex.

y = ( 7 2 ) 2 − 7 ( 7 2 ) + 2 = 49 4 − 49 2 + 2 = 49 − 98 + 8 4 = − 41 4

Therefore, the coordinates of the vertex are ( 7 2 , − 41 4 ) .

Now, substitute a few more x -values in the equation to get the corresponding y -values.

x y = x 2 − 7 x + 2
0 2
1 − 4
2 − 8
3 − 10
5 − 8
7 2

Plot the points and join them to get the parabola.

Worksheet graphing quadratics from standard form find the vertex axis of symmetry answers

Example 2:

Graph the parabola y = − 2 x 2 + 5 x − 1 .

Compare the equation with y = a x 2 + b x + c to find the values of a , b , and c .

Here, a = − 2 , b = 5 and c = − 1 .

Use the values of the coefficients to write the equation of axis of symmetry.

The graph of a quadratic equation in the form   y = a x 2 + b x + c has as its axis of symmetry the line x = − b 2 a . So, the equation of the axis of symmetry of the given parabola is x = − ( 5 ) 2 ( − 2 ) or x = 5 4 .

Substitute x = 5 4 in the equation to find the y -coordinate of the vertex.

y = − 2 ( 5 4 ) 2 + 5 ( 5 4 ) − 1 = − 50 16 + 25 4 − 1 = − 50 + 100 − 16 16 = 34 16 = 17 8

Therefore, the coordinates of the vertex are ( 5 4 , 17 8 ) .

Now, substitute a few more x -values in the equation to get the corresponding y -values.

x y = − 2 x 2 + 5 x − 1
− 1 − 8
0 − 1
1 2
2 1
3 − 4

Plot the points and join them to get the parabola.

Worksheet graphing quadratics from standard form find the vertex axis of symmetry answers

Example 3:

Graph the parabola x = y 2 + 4 y + 2 .

Here, x is a function of y . The parabola opens "sideways" and the axis of symmetry of the parabola is horizontal. The standard form of equation of a horizontal parabola is x = a y 2 + b y + c where a , b , and c are all real numbers and   a ≠ 0 and the equation of the axis of symmetry is y = − b 2 a .

Compare the equation with x = a y 2 + b y + c to find the values of a , b , and c .

Here, a = 1 , b = 4 and c = 2 .

Use the values of the coefficients to write the equation of axis of symmetry.

The graph of a quadratic equation in the form   x = a y 2 + b y + c has as its axis of symmetry the line y = − b 2 a . So, the equation of the axis of symmetry of the given parabola is y = − 4 2 ( 1 ) or y = − 2 .

Substitute y = − 2 in the equation to find the x -coordinate of the vertex.

x = ( − 2 ) 2 + 4 ( − 2 ) + 2 = 4 − 8 + 2 = − 2

Therefore, the coordinates of the vertex are ( − 2 , − 2 ) .

Now, substitute a few more y -values in the equation to get the corresponding x -values.

y x = y 2 + 4 y + 2
− 5 7
− 4 2
− 3 − 1
− 1 − 1
0 2
1 7

Plot the points and join them to get the parabola.

Worksheet graphing quadratics from standard form find the vertex axis of symmetry answers