Day 2

• Objective: Students will solve a system of equations using substitution.
• If you know an x or y value, you can plug it in to the other equation and solve for the variable that you didn't know.
• This can be helpful if you are in business situations.  An example is as follows: you work at a museum and adult tickets are $5 and kid tickets are $3.  1000 people attended the museum that day and you collected $4,670. You need to find out how many adult tickets you sold and how many kids tickets you sold. To solve this, you can create two equations and use substitution to solve for the two variables. (a+k=1000....5a+3k=4,670) 

Quiz!!

1.) Solve the system using substitution:

y=3x-7

8=2y+x

2.) Solve the system using substitution:

y=8x-4

2=2y-8

3.) Solve the system using substitution:

                                                      y=5x-1

                                                      8=4x=y      

Answers to Quiz:

1.) You take the y value and plug it into the equation to solve for x and y. (see image below) 

2.) You take the y value and plug it into the equation to solve for x and y. (see image below)

3.) You take the y value and plug it into the equation to solve for x and y.  (see image below)

For more on how to solve a system of equations by using substitution watch this: http://youtu.be/KNwwu5wjcaA