MICRO LESSON 1
Meaning of Two Variables
Picture it:
A shop sells pens and notebooks.
Simple:
An equation can contain two unknowns such as x and y.
Example:
2x+3y=12.
Quick Check:
Name the variables in 4x+y=9.
MICRO LESSON 2
Linear Form
Picture it:
A straight-line equation has variables only to power 1.
Simple:
The standard form is ax+by+c=0.
Example:
2x+3y-6=0.
Quick Check:
Is x²+y=5 linear?
MICRO LESSON 3
Solution Pair
Picture it:
Different pairs may satisfy the same equation.
Simple:
A solution is an ordered pair that makes the equation true.
Example:
For x+y=5, (2,3) is a solution.
Quick Check:
Does (1,4) satisfy x+y=5?
MICRO LESSON 4
Infinitely Many Solutions
Picture it:
A line contains endlessly many points.
Simple:
A linear equation in two variables usually has infinitely many solutions.
Example:
x+y=4 gives (0,4),(1,3),(2,2)...
Quick Check:
Give another solution of x+y=4.
MICRO LESSON 5
Making a Table
Picture it:
Choose x values and calculate y.
Simple:
A value table gives points for the graph.
Example:
For y=2x+1, x=0 gives y=1.
Quick Check:
Find y when x=2.
MICRO LESSON 6
Plotting the Graph
Picture it:
Each solution becomes a point.
Simple:
Plot two or more points and join them.
Example:
(0,1),(1,3),(2,5) lie on y=2x+1.
Quick Check:
What shape is the graph?
MICRO LESSON 7
Checking a Point
Picture it:
Substitution confirms whether a point lies on the line.
Simple:
Replace x and y in the equation.
Example:
For 2x+y=7, (3,1) works.
Quick Check:
Does (2,3) satisfy 2x+y=7?