Ch.3

Solve by elimination
-12x-4y= -8 
  -6x-2y= -4

• no solution 
• (0,0)
• infinite solutions 
• (4,0)

If a system of linear equations has one solution, what does this mean about the two lines? 

• Parallel lines
• the same line 
• Intersecting lines

Parallel Lines never intersect because...

• they have the same slopes. 
• they have the same y-intercept.
• they have different slopes.
• they have different y-intercepts. 

What is the solution?

• One Solution
• No solution
• Infinitely Many Solutions

If a system of equations has no solution, what does the graph look like? 

• intersecting lines
• parallel lines
• skew lines
• intersecting lines

What variable do you eliminate, and what do you multiply the equation(s) by?

5x + y = 9

10x − 7y = −18

• You eliminate x, and multiply the top equation by 11

• You eliminate y, and multiply the top equation by 7

Which is the correct equation for the graph?

• x-2y=-6
• Y=-6x+6
• Y=-6x-6
• x+y=6

^{What is the solution?} 

• 1
• -2
• (1, 2)
• (1, -1)

Which of these lines has a slope of -3?

• A
• B
• C
• D

Solve:
y = 2x -11
-3y = -6x -15

• (-1.5,-4)
• (1.5,4)
• No solution (parallel lines)
• Infinitely many solutions