Graphing Linear Inequalities Describes a region of a
Graphing Linear Inequalities Describes a region of a coordinate plane. When the inequality is “greater than or equal to” or “less than or equal to” (≥, ≤) the boundary line is solid. When the inequality is “greater than” or “less than” (>, <)the boundary line is dashed. When the inequality is written y > or y ≥ the points above the boundary line are solutions. When the inequality is written y < or y ≤ the points below the boundary line are solutions.
Steps to graphing a linear inequality 1. Graph the boundary line (either solid or dashed) in slope-intercept form. 2. We now have two half-planes. Test a point to find whether it is a solution to the inequality. 3. Shade the half plane that has true solutions.
Graph this! y < 3 x + 4
Graph this! 3 x - 2 y ≤ 6
Let’s Try Graphing Some Linear Inequalities! https: //www. khanacademy. org/math/algebra/linear-equations-andinequalitie/graphing-linear-inequalities/e/graphing_inequalities_2
You have relatives living in both the United States and Mexico. You are given a prepaid phone card worth $50. Calls within the continental United States cost $. 20 per minute and calls to Mexico cost $. 60 per minute. • Write an inequality to represent this situation • Graph the inequality • What are some possible solutions?
Writing an Inequality from a graph https: //www. khanacademy. org/math/algebra/linear-equations-andinequalitie/graphing-linear-inequalities/e/graphs_of_inequalities
Exit Slip
Solving Systems of Linear Inequalities The solutions to a system are contained in the intersection of the shaded region of all inequalities in the system.
Sarah is selling bracelets and earrings to raise money for a non-profit in her community. The bracelets cost $2 and earrings cost $3. She needs to make at least $500. How many bracelets and earrings could Sarah sell to meet her goal? • Write an inequality to represent the income from the jewelry sold. • Sarah knows she will sell more than 50 bracelets. Write an inequality to represent this situation. • Graph the inequalities. • What are possible solutions?
https: //www. khanacademy. org/math/algebra 2/systems_eq_ineq/systems _inequalities_precalc/e/graphing_systems_of_inequalities_2
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