Use graphing to solve. 1. x + y = 6 3x – 4y = 4 Use substitution to solve. 2. y= 2x – 4 x – 5y = 14 Use elimination to solve. 3. 2x – 5y = 1 3x – 4y = -2 Solve. 4. Greg is a star player on the basketball team. In one game, his field-goal total was 20 points, made up of 2-point and 3- point baskets. If Greg made a total of 9 baskets, how many of each type did he make?

Lesson 3.3 Linear Inequalities in Two Variables

 Linear inequalities can be used to model real- world situation, such as the distance that a car with given fuel- economy ratio can be driven using no more than 20 gallons of gas.

 Solve and Graph a linear inequality in two variables.  Use a linear inequality in two variables to solve real-world problems.

A linear inequality in two variables, x and y, is any inequality that can be written in one of the forms below, where A≠0 and B ≠ 0. Ax +By ≥ C Ax + By > CAx + By ≤ C Ax + By < C A solution of a linear inequality in two variables, x and y, is an ordered pair (x,y) that satisfies the inequality. The solution to a linear inequality is a region of the coordinate plane and is called a half- plane bounded by a boundary line.

Find the solution to the linear equation. y < x + 2 Step 1: Graph the line. Use a dotted line for > or <. Substitute (0,0) in the linear equation. If true, shade the side that contains The point (0,0). If false, shade the opposite side. The solution is ALL the ordered pairs in the shaded region.

Find the solution to the linear equation. y – 5 ≤ 2x Step 1: Solve for y. Graph the line. Use a solid line for ≤ or ≥. Substitute (0,0) in the linear equation. If true, shade the side that contains The point (0,0). If false, shade the opposite side. The solution is ALL the ordered pairs in the shaded region.

#1 y< -x #2 2x + 2y > 6

Write the inequality represented by each graph.

Lesson 3.3 Page 950 (1-24)