Linear Equations (Tricky Graphs)

Which graph is y = 1

• 
• 
• 
• 

Answer explanation

y = 1

There is no "x" so the slope is ZERO

You want a horizontal line a

y = 1

Which graph is x = 1

• 
• 
• 
• 

Answer explanation

x = # is always an UNDEFINED graph (vertical line)

You want a vertical line x = 1

Which graph is y = 2

• 
• 
• 
• 

Answer explanation

y = # is a horizontal line. When you have no "x" the slope is ZERO

You want a horizontal line at

y = 2

Which graph is x = 2

• 
• 
• 
• 

Answer explanation

x = # is always a UNDEFINED graph

You want a vertical line at x = 2

Match the following with the correct equation

• y = -3

• 
• x = -3

• 
• x = 3

• 
• y = 3

• 

What is the equation of the following graph?

• y = 5

• y = 5x

• x = 5

• y = 0

Answer explanation

This is a horizontal line, so the slope is ZERO

When there is a zero slope you do not have an "x"

The y-intercept is at 5

So the equation is

y = 5

What is the equation for the following graph?

• x= 4

• y = 4

• y = 4x

• y = 0x

Answer explanation

This is a vertical line, so the slope is UNDEFINED

Undefined line equations are always x = #

You have a vertical line at

x = 4

What is the equation of this line?

• y = -1

• x = -1

• y = -x

• y = 1x

Answer explanation

This is a horizontal line, it has a ZERO slope.

When there is a zero slope you do not have an "x"

The y-intercept is at -1

So the equation is y = -1

What is the equation of this line?

• x = -5

• y = -5

• y = -5x

• x = 5

Answer explanation

This is a vertical line, so the slope is UNDEFINED

Undefined line equations are always x = #

You have a vertical line at

x = -5

Match the following graph with the correct equation

• y = -2x

• 
• y = -x

• 
• y = x + 1

• 
• y = x

• 
• y = -x + 3

•