1.   1) Please graph the following lines on the same graphs:  A) y = 3x - 2B) -2x + y = 4 y = x + 2 y = x + 2 Warm Up

2. Solving Systems by Graphing

3.   A system of equations is two or more equations graphed on the same coordinate grid.  What is the solution?  >>>> It is the point (ordered pair) where the two equations meet. This place means that both equations have the same value at that point.  What is the solution to the system we graphed in A on our warm up? What does it mean?  What is the solution to the systems we graphed in B? What does it mean? What is a system of equations?

4.   How do we check the answer (solution) to our system?  >>>>>>PLUG IT IN!!!  Be careful! Make sure you keep track of x and y and plug the values into the correct variable in the equation!  Check your solutions to the warm up……  ALL ANSWERS ARE GIVEN IN ORDERED PAIR FORM!!!! Checking our answers!

5.   Special solutions occur when we don’t have our two lines crossing at one point.  No solution: When you have parallel lines, they will never cross. Since our solution is the point where both lines cross and there isn’t one, there is no solution. **Check the slopes!**  All Real numbers/Infinite Solutions: When we graph two lines, but only see one on our graph, we have infinite solutions. Since our solution is the point where both lines cross or touch, and these two lines touch at every point, any of the points can work for the answer. What are special solutions?

6.   Graph: 2x – y = 2 y = ½ x + 1  Graph: y = 2x + 2 -y = -2x + 1 Let’s try it!

7.   Scientists studied the weights of two alligators over a period of 12 months. The initial weight and growth rate of each alligator were:  Gator 1: Gator 2: Initial weight: 4 lbInitial weight: 6 lb Growth rate: 1.5lb per Growth rate: 1 lb permonth  After how many months did the alligators weigh the same amount? What was the weight? Write and solve

8.   One satellite radio service charges $10 per month plus an activation fee of $20. A second service charges $11 per month plus an activation fee of $15. In what month was the cost of each service the same? What was the amount? Write and solve #2