Writing Equations in Slope-Intercept Form

What students learn

Students learn to write y = mx + b from a slope and a point, two points, a graph or a story, with b read off the y-axis.

See inside

Watch out

A line has slope 1/2. It crosses the x-axis at 6 and the y-axis at −3. Lee writes its equation.

The mistakes it targets

• Reads b off the x-axis instead of the y-axis
• Swaps the slope and the y-intercept
• Uses a point's y-value as b
• Gives a falling line a positive slope

The interactive Teacher Deck (32 slides, PowerPoint)

• The Learn page taught on screen: 8 fill-in blanks, each filled on its own click as students write it
• The worked example one slide per step (four steps), each with the reason for the step
• Six practice and three apply problems: a your-turn slide with a think-time bar, then the solution one line per click
• Jump buttons on every slide: go straight to any problem, the answer bank or the exit ticket
• Speaker notes on each problem: the question to ask, the worked answer and the common error to listen for
• A completed deck PDF (19 pages) with every slide fully built, to print or post

The student packet (9 pages)

• Learn: guided notes with four definitions, the key rule, a worked example and a Watch Out error pair
• Practice: two warm-up, two standard and two stretch problems, with an answer bank for self-checking that hides three common-mistake decoys
• Apply: one word problem, a reasoning prompt and one error analysis
• Assess: an exit ticket of four items, two per page, with an I-can self-rating
• Homework (page 5): eight new problems, two warm-up, four standard and two stretch
• Answer key (pages 6–7): every problem worked step by step, four common mistakes with what to do about each, and a grading guide, plus the homework key (page 8)
• Color and ink-saver editions of the whole packet