4.1 Review of Graphing Quadratic Functions in Standard Form
Review 4.1 Graphing a Quadratic Function in Standard Form
In this activity we are going to review how to graph a parabola when the function is in Standard Form.
Let's start with some warm-up questions. Just answer what you think. I am the only one who can see your responses.
Question 1
What is the minimal number of points we want for graphing a parabola.
Question 2
What are the five (5) points?
Steps
Lets review the steps for graphing a function in standard form.
Step 1: Identify the coefficients of the function.
Step 2: Find the vertex. Calculate the x-coordinate.
Then find the y-coordinate of the vertex.
Question 3
How do we find the y-coordinate of the vertex?
Notes continued
Step 3: Draw the axis of symmetry.
Step 4: Identify the y-intercept, . Plot the point . Then reflect this point in the axis of symmetry to plot another point.
Question 4
How many points do we have now?
Steps (cont.)
Step 5: Evaluate the function for another value of . Plot this new point and its reflection in the axis of symmetry.
Step 6: Draw a parabola through the plotted points.
Question 5
What does it mean when you are asked to find the "roots"?
Question 6
How do you find the roots?
Example
Practice the six (6) steps for graphing a quadratic function.
Graph .
Do all of the calculations and work in your notebook.
Step 1
Identify the coefficients of
Step 2
Find the vertex?
Step 3
Draw the axis of symmetry. What is the equation for the axis of symmetry?
Step 4
Indentify the y-intercept for
Step 5
Evaluate the function for another value of x. (choose your own).
Step 6
Draw a parabola through the plotted points.
Use the graph below to draw a parabola.
OPTION 1:
1. Plot your vertex.
2. Draw your axis of symmetry.
3. Plot your y-intercept and its reflection. Use 
if you need to adjust your window.
4. Plot your points from Step 5.
OPTION 2:
1. Type your coordinates and equation for the axis of symmetry directly into the input window.
2. Draw your axis of symmetry.
3. Plot your y-intercept and its reflection. Use if you need to adjust your window.
4. Plot your points from Step 5.
OPTION 2:
1. Type your coordinates and equation for the axis of symmetry directly into the input window.
Finishing Your Graph
Scroll back up to your graph. Type into the Input Bar at the left of your graph. Does the parabola go through your five (5) points?
If YES, nice job!
If NO, double check you calculations for the points it missed.