Section 6: Solving Systems of Equations with Graphing Unit 1: Everything Linear Homework: pg 141 #3-9, 69 – due Tuesday Learning Target: Students will solve systems of equations by graphing and relate to real- world situations.

Ex 1: Solve y = -3x + 2 for x and y. y = 2x - 3 Graph both equations. Find where they meet each other. (, ) Check your solution in both equations.

Ex 2: Solve y = ½x -3 for x and y. y = 2x Graph both equations. Find where they meet each other. (, ) Check your solution in both equations.

Ex 3: Solve y = -½x + 4 for x and y. y = -½x - 5 Graph both equations. Find where they meet each other. What do you think your solution is this time?

Ex 4: Use the graphing calculator to predict at what year men and women will live to an equal age. YearMen (Years)Women (Years) U.S. Life Expectancy at Birth

Directions for graphing calculator. Re-number the years starting by changing 1970 to 0, then 1975 is 5, and so on. Go to STAT and EDIT. Enter the chart into L1, L2 and L3. To get the equation for the Men through the Years: Hit STAT Go over to CALC Hit LINREG (ax+b) L1, L2*the comma is above 7 *L1 is above 1 *L2 is above 2 Hit ENTER and write the equation (round 3 decimal places) To get the equation for the Women through the years: Hit STAT Go over to CALC Hit LINREG (ax + b) L1, L3 Hit ENTER and write the equation. Go to Y= and enter both equations into the calculator. Hit ZOOM and ZOOMFIT (this is 0) Hit 2 ND and TRACE and INTERSECT (5) Hit ENTER 3 times Round the x-value to the nearest whole number and figure out which year that would be

HOMEWORK Pg 141 #3-9, 69 * Due on Tuesday

Ex 2: Solve y = ½x -3 for x and y. 3x + 2y = 2 Graph both equations. Solve 2 nd equation for y = mx + b Find where they meet each other. (, ) Check your solution in both equations.

Ex 2: Solve y = 5/3 x - 2 for x and y. 10x - 6y = 12

What is the difference between Many Solutions and No Solutions? Describe what their equations look like and what their graphs look like.