1. Collegial Sharing – Leanne Schrier
Course: Algebra 1
Unit 2: Graphing Linear Equations & Inequalities
Activity: What Went Wrong?
Skills from Unit 2:
Put an equation into slope intercept form.
Identify the slope as an improper fraction.
Classify the slope as positive, negative, zero, or undefined.
Identify the y-intercept as an ordered pair.
Plot the y-intercept.
Use slope to plot additional points and graph a line.
Show work to calculate slope.
Calculate slope given two points.
Calculate rate of change from an application problem.
Interpret rate of change.
Review Skills from Unit 1:
Write a compound inequality.
Graph a compound inequality.
Mathematical Practice Standard Focus:
3) Construct viable arguments and critique the reasoning of others.

2. Problem 1 – Find 2 Mistakes
Algebra 1 Names: __________________________________
Unit 2 – What Went Wrong? Date: ___________________________________
Each of the problems have been completed incorrectly. Each problem has TWO SEPARATE ERRORS.
Your job is to:
Complete the problem correctly (CREATE AN ANSWER KEY).
Compare your work to the incorrect work and assess the work “correct with error.” Rate each skill with a 1, 2, or 3 as discussed in class.
Explain what the mistakes were and how you fixed each in complete sentences (at least one sentence per mistake).
Problem 1 – Find 2 Mistakes
Directions: Graph the line y = 3x State the slope and y-intercept. Classify the slope as positive, negative, zero, or undefined.
ANSWER KEY
Directions: Graph the line y = 3x State the slope and y-intercept. Classify the slope as positive, negative, zero, or undefined.
Slope: ____________________________
Y-Intercept: _______________________
Classify Slope: ______________________
Checklist of Skills:
_____ Identify Slope
_____ Identify Y-Intercept
_____ Classify the Slope
_____ Plot Y-Intercept
_____ Graph Using Slope
Explanation: ____________________________________
__________________________________________________________________________________________________________________________________________
____________________________________________________________________________________________

3. Problem 2 – Find 2 Mistakes ANSWER KEY
Directions: Calculate the slope between the points (2, 7) and (2, -1). Classify the slope as positive, negative, zero, or undefined.
ANSWER KEY
Directions: Calculate the slope between the points (2, 7) and (2, -1). Classify the slope as positive, negative, zero, or undefined.
Slope: _______________________________
Classify Slope: ________________________
Checklist of Skills:
_____ Show work for calculating Slope.
_____ Calculate Slope.
_____ Classify Slope.
Explanation: ________________________________ ______________________________________________________________________________________________________________________________
Problem 3 – Find 2 Mistakes
In 1958, the painting Still Life with Apples by Paul Cezanne sold at auction for $252,000. Then, in 1993 it sold again for $28,600,000.
a) Write a compound inequality to illustrate the values of the painting between 1958 and Graph the inequality on a number line.
b) Calculate and label the rate of change for the value of the painting between 1958 and 1993.
ANSWER KEY
In 1958, the painting Still Life with Apples by Paul Cezanne sold at auction for $252,000. Then, in 1993 it sold again for $28,600,000.
a) Write a compound inequality to illustrate the values of the painting between 1958 and Graph the inequality on a number line.
b) Calculate and label the rate of change for the value of the painting between 1958 and 1993.
Checklist of Skills:
_____ State a compound inequality (AND).
_____ Graph a compound inequality (AND).
_____ Show work for calculating rate of change.
_____ Calculate rate of change.
_____ Label rate of change.
Explanation: ____________________________
________________________________________________________________________________________________________________________________________________________

4. Problem 4 – Find 2 Mistakes
Directions: Graph the line 2x + 4y = 8. State the slope and y-intercept. Classify the slope as positive, negative, zero, or undefined.
ANSWER KEY
Directions: Graph the line 2x + 4y = 8. State the slope and y-intercept. Classify the slope as positive, negative, zero, or undefined.
Slope: ____________________________
Y-Intercept: _______________________
Classify Slope: ______________________
Checklist of Skills:
_____ Put the equation in slope-intercept form.
_____ Identify Slope
_____ Identify Y-Intercept
_____ Classify the Slope
_____ Plot Y-Intercept
_____ Graph Using Slope
Explanation: ____________________________ _______________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________