Direct Variation Equation

What is the equation for the given graph?

What is the equation for the given graph?

What makes a graph proportional?

• A straight line (linear) that goes through the origin

• Linear (straight line), that does NOT go through the origin.

The constant of proportionality in the equation y = ½x is _______.

• 1/2

• x

• y

• 2

Which of the following is an equation for this relationship?

• y=90x

• y=25x

• y=45x

• y=2x

If the constant of proportionality is 7, which of the following is the correct proportional equation?

• y=7k

• y=k7

• y=kx

• y=7x

Identify the constant of proportionality. Write your answer as y=kx

• y=14x

• y=7x

• y=2x

• y=6x

Identify the constant of proportionality. Write your answer as y=kx

• y=7x

• y=72x

• y=9x

• y=8x

Write an equation for this relationship.

• y=18x

• y=18.50x

• y=22.50x

• y=22x

Identify the constant of proportionality and use it to write the equation.

• y = 5x

• y = 1/5x

• y = x

• y = 2.5x

• none (not proportional)