8.EE.B. Understand the connections between proportional relationships, lines, and linear equations.

• Different Areas?
• DVD Profits, Variation 1
• Equations of Lines
• Find the Change
• Folding a Square into Thirds
• Proportional relationships, lines, and linear equations
• Stuffing Envelopes

8.EE.B.5. Graph proportional relationships, interpreting the unit rate as the slope of the graph. Compare two different proportional relationships represented in different ways. For example, compare a distance-time graph to a distance-time equation to determine which of two moving objects has greater speed.

• Coffee by the Pound
• Comparing Speeds in Graphs and Equations
• Peaches and Plums
• Sore Throats, Variation 2
• Stuffing Envelopes
• Who Has the Best Job?

8.EE.B.6. Use similar triangles to explain why the slope $m$ is the same between any two distinct points on a non-vertical line in the coordinate plane; derive the equation $y = mx$ for a line through the origin and the equation $y = mx + b$ for a line intercepting the vertical axis at $b$.

• Slopes Between Points on a Line