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Warm - Up. Solve the system algebraically: x + ½y = 5 3y – 2x = 6. Chapter 3.3. Solving Systems of Inequalities by Graphing. Solve a system of inequalities by graphing:. Just like before, in order to graph – you must first rewrite the equations in slope-intercept form Y=mx + b.
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Warm - Up • Solve the system algebraically: x + ½y = 5 3y – 2x = 6
Chapter 3.3 Solving Systems of Inequalities by Graphing
Solve a system of inequalities by graphing: Just like before, in order to graph – you must first rewrite the equations in slope-intercept form Y=mx + b
Graph the first equation • The first equation is already in slope-intercept form. • Remember that the line must be solid since the inequality is also equal to • Then pick a test point: For example, choose (0,0) since it is not on the line itself. Substitute in for (x,y) • 0≥3(0)-2 0≥-2 ? Yes
Rewrite Second Equation • 2x – 4y < 12 • - 4y < - 2x + 12 • y > ½ x - 3 • Pick test point to see what side is shaded.
Graph the second equation on the same graph as the first The solutions lie within the area where the two shadings overlap
You Try! First: Rewrite the equations Second: Graph the equations Third: Pick a point to decide the shading
Tonight’s Homework: Page 126 (12-19) ON GRAPH PAPER Quiz – Elimination/Substitution Next Class