Solving System of Equations Using Elimination

Solve the system of linear equations using the elimination method.

$$-x+y=4$$  

$$x+3y=4$$  

What operation do you think would eliminate the "x" variables in the system: 

$$2x+3y=6$$  
$$-2x+8y=16$$  

When we add the two equations, what is the new equation we've created ? 

$$3x+2y=7$$  

$$-3x+4y=5$$  

Now that we have 6y=12, what do you think we do ? 

$$3x+2y=7$$  

$$-3x+4y=5$$  

Look at the system of equations. How do you think you could start solving it. 

$$5x-3y\ =\ 16$$  
$$x-3y=8$$  

If we multiply the bottom equation by negative one, what would that new equivalent equation be ? 

$$5x-3y\ =\ 16$$  
$$x-3y=8$$  

What type of elimination could you use for this system of equations?

𝑥 − 6𝑦 = −18

−𝑥 + 10𝑦 = 30

What type of elimination would fit best for this system of equations?

6x + 5y = 4

6x – 7y = –20

Describe the error in solving the system of equations using elimination: