Systems of Equations Graphing and Substitution Practice

What does it mean to substitute?

• to remember

• to replace or to plug in

• to get rid of or to take away

• to connect the dots

For equations below, which method is easier to use? Why?

• Graphing, because both are already in y = mx + b form.

• Substitution, because one equation is already solved for y. 

• Elimination, because both are already in ax + by = c form. 

• None. 

For equations below, which method is easier to use? Why?

• Graphing, because both are already in y = mx + b form. Also, substitution, because one equation is already solved for y. 

• Elimination, because both are already in ax + by = c form. 

• Elimination, because both are already in ax + by = c form. Also, graphing, because both are already in y = mx + b form. 

• None.

What is the solution?

• (6, 3)

• (3, 6)

• (-6, 3)

• No solution

How many solutions?

• One Solution

• No solution

• Infinitely Many Solutions

The graph above represents the allowance that Stefin and Daniel receive every week. If the x-axis represents the number of weeks and the y-axis represents the earnings ($), what is the amount of earnings that both boys will have the same?

• $4

• $2

• $6

• $8

The solution (x, y) to a system of equations is the point where they...? 

• Run off the graph

• Don't touch

• Intersect

• Exist

Solve  the system of equations.  
   x + 5y = -27
-2x - 5y = 24

• (3, 6)

• (-3, -6)

• (-3, -4)

• (3, -6)

-4x-2y=-12
4x+8y=-24

• (5,6)

• (6,-6)

• (6,-2)

• (4,-3)

Which of these is NOT one of the methods I showed you for solving systems of linear equations?

• Elimination

• Substitution

• Graphing

• Frustration