Solving Systems by Elimination

Solve by elimination:
4x+9y=28
-4x-y=-28

• (-7,0)
• (6,0)
• (-6,0)
• (7,0)

4x +  8y = 20
-4x + 2y = -30
Which variable will be eliminated?

• The  x
• The  y
• The  z
• The unknown

Solve by elimination:
7x+y=-9

-3x-y=5

• No solution
• (1,8)
• (-2,-3)
• (-1,-2)

What would be the first step in finding the solution with elimination?

4x + 3y = 1

x - 3y = -11

• cross out the 3y and -3y

• cross out the 4x and x

• change all the signs of the second equation

• add 1 and -11

Identify the solution to this system of equations.

• (4, -1)
• (-1, 4)
• (-4, 1)
• (-4, -1)

A ________________ is a set of two or more equations that have the same variables.

• solution of a system
• elimination method
• system of equations
• table

How many solutions does the following equation have?
3x − 3 = −3 + 3x

• One Solution
• No Solutions
• Infinitely Many Solutions

Which variable will be eliminated?

• x

• y

What do you have to multiply the first equation by to have the x's be opposite and the same?

• 3

• 2

• -2

• -3

Solve the system of Equation (x,y)
x + 4y = –3
 x + 7y = –12 

• (-3,9)
• (9,-3)
• (3,9)
• (9,3)