Introduction to Linear Equation Graph

Introduction

• The general equation is: Y = ax + b
• • Y: Dependent Variable
  • a: Slop
  • x: Independent Varialbe
  • b: Y-intercept
• Has a straight line graph
• Use the x-axis for the independent variable x
• Use the y-axis for the dependent variable y

Example:

• Where x is the monthly sales, in dollars, and y is the monthly income, in dollars.
• Draw an accurate graph of this equation for x=0 to x= 20,000. use the horizontal axis for x and the vertical axis for y.

Slope

• Is a measure of the direction of the line
• Positive slope = moving up line
• Negative slope = heading down line
• A slope of 0 (zero) = flat horizontal line
• Slope Formula : a = (y₂ − y₁) / (x₂ − x₁) = ∆y / ͧ0x
• (x₁,y₁) and (x₂,y₂) are only two points located on the line
• The slope measures the change in the dependent variable y for every change in the independent variable x