Review 8th

In order to be a function the following must be true.

• each x value has only one y value
• each y value has only one x value
• each x  has only one y & each y has only one x 
• each x and y are equal

• Function
• Not a Function

• Function
• Not a Function

• Function
• Not a Function

• Function
• Not a Function

• It is a function because no vertical lines hit it twice.
• It's not a function because a vertical line hits it twice.
• It's not a function because no vertical lines hit it twice.
• It is a function because a vertical line hits it twice.

• Function
• Not a Function

Does this graph represent a proportional relationship?

• Yes, because the line is pretty.
• No, because the line goes through the origin.
• Yes because the line goes through the origin.
• No, because the graph is non-proportional.

What is the y-intercept for the following graph and is it proportional or non-proportional?

• Proportional, b=1
• Proportional, b=-2
• Non-proportional, m= -1
• Non-proportional, b=1

Find the slope of the line that passes through the points (2, 4) and (6, 12) (hint use formula y2-y1/x2-x1)

• 1/2

• -1/2

• 2

• -2