1. Solve Linear Systems By Elimination

2. Elimination (Keys to solving)
Things you need to solve by elimination
Same coefficient of the same variable
Opposite signs of the like variable
When the system is added, the variable drops out (gets eliminated)
Continue solving for the other variable by substitution

3. Solve by Elimination Follow Steps
Do we have the same coefficient of one of the variables?
Does that variable have opposite signs in each equation?
Add the two equations together and one of the variables will drop out.
Additive Inverse
Solve for the other variable using the substitution method

4. Solve by Elimination Follow Steps
Do we have the same coefficient of one of the variables?
Does that variable have opposite signs in each equation?
Add the two equations together and one of the variables will drop out.
Additive Inverse
Solve for the other variable using the substitution method

5. Solve by Elimination Follow Steps
Do we have the same coefficient of one of the variables?
Does that variable have opposite signs in each equation?
Add the two equations together and one of the variables will drop out.
Additive Inverse
Solve for the other variable using the substitution method

6. Solve by Elimination Follow Steps
Do we have the same coefficient of one of the variables?
Does that variable have opposite signs in each equation?
Add the two equations together and one of the variables will drop out.
Additive Inverse
Solve for the other variable using the substitution method

7. Creating Perpendicular Lines (have a 90° angle of intersection)
When creating perpendicular lines, all you need to know is the slope of the original line
The y-intercept does not matter
Once you know the “m” (slope) you take the negative reciprocal of the given slope
This means the opposite sign and flip the slope fraction
One line will have a positive slope and the other will have a negative slope

8. Find the Equation of a Perpendicular Line
Original (given) equation of a line
Sign _______
m = _______
Now fill in for the perpendicular line
Write the equation of the perpendicular line

9. Assignment
Worksheet