Download 3.1/3.2 Solving Systems of Equations by Substitution Method

 3.1/3.2 Solving Systems of Equations by Substitution Method
DAY 2
There are 4 ways to solve systems of equations:
1. Graphing
2. Substitution Method
3. Addition/Subtraction Method
4. Multiplication/Addition Method
Solve each by Substitution
1. x+y=2
y=x+8
2. 3x+2y=2
y=x­4
4
Solve each by Substitution
5
3.2
DAY 2
Solving Systems of Equations using the Substitution Method
Notes Completed
There are 4 ways to solve systems of equations:
1. Graphing
2. Substitution Method
3. Addition/Subtraction Method
4. Multiplication/Addition Method
Solve each by Substitution
1. x+y=2
y=x+8
2. 3x+2y=2
y=x­4
4
Solve each by Substitution
5
Algebra 2 3.1/3.2 Substitution Method
Example:
3x+3y=6 y=x+2
3x+3y=6 3x+3(x+2)=6 3x+3x+6 =6 3x+3y = 6 6x+6=6 3(0)+3y = 6 0+3y = 6 ­6 ­6
3y = 6 6x = 0 3 3 6 6 y = 2 x = 0 (0,2) 1. Draw line under original problem
2. Rewrite the equation written in Standard Form (Ax+By=C)
3. Rewrite the equation again with the substitution and solve eq for the variable still showing Note: if the second eq is solved for "y", substitute this value in for "y". If the second eq is solved for "x", substitute this value in for "x".
4. Still need second part of ordered
pair. Draw an arrow back to standard form equation and use this eq to find other part of ordered pair answer
Answer
Solve each using Substitution: Do all work on looseleaf. Write the problem first, then show all work. Write your final answer next to the problem on this worksheet. 1. 4x+2y=6 y=3x+8
5. 2x+3y=15 x=y+1 2. 2x+y=1 y=3x­3 6. 2x+4y=10 x=3y­1 3. y=3x­15 x+2y=­2 7. x=2y+1 2x+y=10 4. 3x+y=7 x=y+9
8. x=3y+2 2x+4y=24