Presentation on theme: "Solving Systems with 2 Variables U3.1. Vocabulary A system of linear equations in two variables x and y, also called a linear system, consists of two."— Presentation transcript:
Solving Systems with 2 Variables U3.1
Vocabulary A system of linear equations in two variables x and y, also called a linear system, consists of two or more equations that can be written in the following form. Ax + By = C Dx + Ey = F A solution of a system of linear equations in two variables is an ordered pair (x,y) that satisfies each equation.
Example 1. Solve by graphing y = -x + 5 Solve by Graphing -2y = -3x + 20 y = 3/2 x -10 The solution is the point of intersection which is (6, -1).
Classifying Systems System with at least one solution: is called Consistent. Exactly one solution is consistent - independent Infinitely many solutions is consistent - dependent System with no solution: is called Inconsistent. Consistent Independent (Intersecting) Consistent Dependent (Same graph) Inconsistent (Parallel) EX2.EX3. EX4.
Practice Graphing Solve the system by graphing. Then classify the system as consistent and independent, consistent and dependent, or inconsistent. 1.-2x +y = 5 y = -x x - 2y = 10 3x - 2y = x + 5y = 6 4x +10y = 12 (-1,3) Consistent and independent No solution; inconsistent Infinitely many solution; Consistent and dependent
Graph systems of Linear Inequalities To graph a system of linear inequalities, follow these steps: ◦ Step 1 – Solve each inequality for y. ◦ Step 2 – Graph each inequality. Pick the type of lines (solid or dotted) Pick where to shade (above or below) ◦ Step 3 – Identify the region of the graph that is shaded for ALL of the inequalities