Proportional relationships

Identify the constant of proportionality.

• k = 2x

• k = 2

• k = 4

• none (not proportional)

How do you know if a table is proportional?

• x-y is the same for each ordered pair

• The cross products are equal

• x + y is the same for each ordered pair

• It has a constant of proportionality

How do you find the constant of proportionality for an equation?

• The number in front of y

• The number in front of x

• The number added to x

• The number subtracted from x

A graph is proportional if...

• It is straight

• It passes through the origin

• Its straight and it passes through the origin

Determine the constant of proportionality for the table. Express your answer as y = kx

• y = 1/2x

• x = 1/2y

• y = 2x

• k = x

What is the constant of proportionality for the following graph?

• 80
• 20
• 40
• 160

What is the constant of proportionality? 

• 45 mph
• 90 mph
• 135 mph
• 2 mph

Write an equation for this situation.

• y=9.75x

• y=19x

• y=19.25x

• y=9.5x

True or False:

The following graph is proportional?

• True

• False

True or False:

The following graph is proportional?

• True

• False