5/13 class

What is your "favorite" way to solve linear systems?

• elimination

• substitution

• graphing

• equal values method

How can you tell if a point is a solution to a system?

• It makes the first equation true.
• The (x,y) coordinates satisfy both equations
• It makes logical sense
• It makes neither equation negative

What is the solution to this system of equations?

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

Solve the system of equations.
x + 2y = -3
x - y = -12

• (-9, 3)
• (-7 ,5)
• (3, 15)
• (9, 6)

Solve the system of equations.
y = 4x+1
3x + 2y = 13

• (1, 5)
• (5, 1)
• (0.25, 2)
• ∅

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

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

On Monday Joe bought 10 cups of coffee and 5 doughnuts for his office at the cost of $16.50.   On Tuesday he bought 5 cups of coffee and 10 doughnuts for a total of $14.25.  Which equations could be used to determine the cost of the coffee? 

• 10c + 5d = 14.25
  5c + 10d = 16.50
• 10c + 5d = 16.50
  5c + 10d = 14.25
• c + d = 10
  5c + 10d = 16.50
• c + d = 5
  5c + 10d = 16.50

When both lines in a system are identical, the system has __________________.

• infinite solutions

• one solution

• no solution

• parallel solutions

• 
• 
• 
• 

• No Solution

• (2, 2)

• (-1, 2)

• (-1, -2)