SME
Grade 8 Math
Functions
Functions: definition, tables and graphs
Main lesson
Is it a function? Mapping diagram
Use this for “Each input is its output squared. Is the output a function of the input?”
Function or not?
Use this for “Is a student’s age a function of the student? Is the student a function of the age?”
Which graph fits the story?
Use this for “Two taps fill a tub, then one is shut. Which graph shows the water?”
Linear functions (y = mx + b)
Main lesson
The equation from two points
Use this for “A line passes through (1, 3) and (2, 5). What is its equation?”
Slope and intercept in a story
Use this for “A bike rental costs $8 plus $3 an hour. What do 5 hours cost, and what do the 8 and the 3 mean?”
Lines written ax + by = c
Use this for “A snack mix uses nuts at $4 a pound and raisins at $2 a pound; $16 in all” or “(4, y) is on 3x + 4y = 24: find y.”
Linear or not?
Use this for “Is the area of a square a linear function of its side?”