MyMathKidK-8 Curriculum

Grade 8 Functions Worksheets

Master functions step by step, from basic concepts to advanced problem solving

Common Core: 8.F

Watch & Learn

Learning Path

Start with Lesson 1 and work your way through!

1

Input-Output Tables

Easy

Complete and analyze function tables

Use a rule or a table to find an output or an inputFind a rule’s rate of change and starting value from a table
2

Linear Functions

Easy

Understand y = mx + b

Identify slope and y-interceptRead a linear function’s graph: slope, y-intercept and points on the line
3

Slope

Easy

Calculate and interpret slope

Calculate slopeInterpret rate of change
4

Comparing Functions

Easy

Compare functions in different forms

Compare tables, graphs, equationsIdentify faster growth
5

Unit Review

Easy

Review all function concepts

Review all conceptsPrepare for assessment

How to solve Grade 8 functions problems

Real problems from these worksheets, solved one step at a time — the same explanations your child sees when practicing online.

  1. Example 1

    A linear function has these values: when x = 0, 1, 2, 3, y = 9, 6, 3, 0. What is y when x = 12?

    1. At x = 0, y = 9, so the y-intercept is b = 9.
    2. Each time x goes up by 1, y changes by 6 − 9 = −3, so the rate of change is −3.
    3. So the rule is y = −3x + 9.
    4. At x = 12: y = −3 × 12 + 9 = −36 + 9 = −27.
    5. So y = −27 when x = 12.

    Answer: −27

  2. Example 2

    A car travels at a constant speed. The graph of distance (miles) against time (hours) is a line through (0, 0) and (3, 120). What is the slope of the line, in miles per hour?

    1. Slope = change in y ÷ change in x (rise over run).
    2. From (0, 0) to (3, 120): change in y = 120, change in x = 3.
    3. Slope = 120 ÷ 3 = 40.
    4. So the slope is 40 miles per hour — the car's speed (its unit rate).

    Answer: 40

  3. Example 3

    Function A is y = 5x + 13 and function B is y = 4x + 19. For what value of x do the two functions have the same value of y?

    1. Set the two rules equal: 5x + 13 = 4x + 19.
    2. Subtract 4x from both sides: x + 13 = 19.
    3. Subtract 13 from both sides: x = 19 − 13 = 6.
    4. Check: A gives 5 × 6 + 13 = 43 and B gives 4 × 6 + 19 = 43.
    5. So x = 6.

    Answer: 6

Frequently Asked Questions

Are these Grade 8 Functions worksheets free?
All printable Functions worksheets on MyMathKid are free to download and print. Answer keys are a premium feature available with a subscription.
How many Functions worksheets are available for Grade 8?
There are 5 progressive Functions lessons with worksheets for Grade 8, covering skills from foundational concepts to advanced problem solving.
Are these Functions worksheets aligned to Common Core?
Yes — Grade 8 Functions aligns with Common Core 8.F (Functions).
What will my child practice with these Functions worksheets?
Your child will practice: Input-Output Tables, Linear Functions, Slope, Comparing Functions, and more.