Linear Relationships & Slope

What you’ll learn

• Slope is the constant rate of change; for proportional relationships it equals the unit rate $k$ in $y = kx$.
• Similar triangles on a line justify using the same rise/run between any two points.
• The form $y = mx + b$ separates steady growth ($m$) from a starting value ($b$).
• Solving $ax + b = c$ undoes operations in reverse order; check by substitution.
• Graphing connects tables, equations, and stories: plot intercept and slope, not random points only.