Inequalities on graphs

• Inequalities can be represented on graphs by shaded regions and dotted or solid lines

• These inequalities have two variables,?x?and?y
• Several inequalities are used at once
• The solution is an?area?on a graph (often called a?region)
• The inequalities can be?linear?or?quadratic

How do I draw inequalities on a graph?

• Sketch each graph
  • If the inequality is?strict (< or >)?then use a?dotted line
  • If the inequality is?weak (≤ or ≥)?then use a?solid line
• Decide?which side?of the line?satisfies?the inequality
  • Choose a coordinate on each side and?test?it in the inequality
    • The origin is an easy point to use
  • If it satisfies the inequality then that whole side of the line satisfies the inequality
    • For example: (0,0) satisfies the inequality y <?x2?+ 1 so you want the side of the curve that contains the origin