Name: Solving the System of
Linear-Quadratic Equations
ACTIVITY/TASK: Solve the system of linear-quadratic equations graphically using
Desmos and ShowMe App.
LEARNING OUTCOME: Participants will learn how to determine and verify the solution of a system of linear-quadratic equations graphically.
You will need a Pre-Calculus 11 textbook or a System of Linear-Quadratic Equations question. In this activity, we will use the following system
of equations as an example.
y = x2 − 2
y = 2x + 1
WHAT YOU WILL NEED: Desmos (graphing calculator app) and ShowMe
(Photos)
1
Debby Kim
Open Desmos.
2
Graph the first equation
y = x2 − 2
using the
keypad.
To graph the equation, tap y  =  x a2  -  2.
May 2015
3
5
Graph the second equation
y = 2 x + 1 by
tapping y  =  2  x  +  1.
Tap the Table icon
values.
to see the table of
4
Tap the Settings icon
for each equation.
to see the table of values
6
You will see two graphs and the table of values for
each equation. Notice that several points have been
plotted on the graph.
Open ShowMe.
7
Debby Kim
Use the
icon to hide the equations and the
table of values. Take a screenshot of the graph.
Your screenshot is now saved in Cameral Roll.
8
May 2015
9
Add the screenshot of the graph from Camera
Roll.
10
Record how you determined the solution of the system
of given equations. Save your work.
POST IT NOTE ACTIVITY: Write Desmos on the top of the post it note. Write one advantage for using Desmos
with a student who has difficulty with solving linear and quadratic equations graphically. How could you get
students using this tomorrow? List one or two other implementation ideas for using Desmos. List 1-2 graphing
activities you could have students create using Desmos.
Debby Kim
May 2015