"Since the mathematicians have invaded the theory of relativity, I do not understand it myself any more." -- Albert Einstein
Linear Equations and Intercepts Section 3.3
Overview Recognizing Linear Equations Intercepts Using Intercepts for Graphs Graphing Horizontal or Vertical Lines
Recognizing Linear Equations Standard form
Intercepts y-intercept x-intercept
Using Intercepts for Graphs Finding x and y intercepts (p. 188) – To find y-intercept of an equation’s graph, replace x with 0 and solve for y – To find x-intercept of an equation’s graph, replace y with 0 and solve for x
Graphing Horizontal or Vertical Lines Standard Form – Ax + By = C What if A or B (but not both) were 0? – If A = 0, then there is no x-term and the graph is a horizontal line – If B = 0, then there is no y-term and the graph is a vertical line
Graphing Horizontal or Vertical Lines Linear equations in one variable (p. 192) – Graph of y = b is a horizontal line With y-intercept (0, b) – Graph of x = a is a vertical line With x-intercept (a, 0)
x y