Ch 5.1 Graphing Systems Objective: To solve a system of linear equations by graphing.

Definition 1)Graph both equations using any method (Table, Intercept, Slope-Intercept) 2)The (x, y) coordinate where the lines intersect is the solution. Rules System (of equations): Two or more equations involving the same variables. Check Your Answers! Plug in the x and y solutions into BOTH equations to verify that they both make TRUE statements.

y = 2x - 1 y = -x + 5 Example rise run rise run 1

y = -x - 1 y = x Example 2 1 rise run rise run 1212

y = x y = x Example rise run rise run 6

Check! y = x + 2 y = x Example rise run rise run 1414

Pam has $120 and is spending $5 every week. Lorenzo has $20 and is saving $7.50 every week. When will they have the same amount of money? Let x = # of weeks Let y = total money Pam Lorenzo weeks total money In 8 weeks = = 30 4 =

Classwork y = - x + 4 y = x - 4 1) y = - x - 3 y = -2x + 2 2)

y = 5x - 2 y = -x + 4 3) x + y = 3 7x + y = -3 4)

x + y = -3 6x + y = 2 5) 3x + y = 4 x - 2y = 6 6)