Solving Systems of Linear Equations

Solve using Elimination. 
 4x + 8y =  20
-4x + 2y = -30

• (-7,1)
• (2,-5)
• (-2,5)
• (7,-1)

Solve by elimination 
  2x + 9y = -7
6x - 3y = 9 

• (-1, -1) 
• (2,-1)
• (1,1)
• (1,-1)

 Solve using elimination.
 7x + 2y = 24
  8x + 2y = 30

• (6,-9)
• (-9,6)
• No solution
• Infinite number of solutions

If two lines are parallel, how many solutions do they have?

• 1
• 2
• infinite
• none

Solve using elimination. 
−4x − 4y = 0
  8x + 8y = 0 

• (−6, −4) 
• Infinite number of solutions  
• No solutions
• (6, 4) 

Solve by elimination:
3x + 7y = 23
-3x - 7y = -17

• No solution
• Infinite number of solutions
• (-3,3)
• (3,3)

The graph of a system of linear equations is shown below. What is the solution of the system? 

• no solution
• infinitely many solutions
• (-3, 0)
• (0, 6) 

What type of solution to at system of equations is shown in the graph?

• one solution
• no solution
• infinitely many solutions

A linear system has one solution when the graphs of the equations ____________________________________.

• A. The lines intersect.
• B. Lines have different slopes and y-intercepts.
• Both A and B
• None of the above

Will the solution (-3, -7) make the following system of equations a true statement? 
y = 4x + 5
y = x – 4

• YES
• NO