Variations

Which of the following table of values represents direct variation?

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Which of the following represents: “y varies inversely to x” ?

Using the table of values for inverse variation, what is the equation of variation?

Which of the following situations illustrates a joint variation?

• The heat required to melt a substance to its mass

• The perimeter of a square to its side

• The speed of the boat per hour to the amount of diesel

• The volume of a rectangular box to its length, width, and height

Suppose y varies jointly as x and z. 
If y = -180 when z = 15 and x = -3, then find y when x = 7 and z = -5.

• -140
• 140
• -4
• 4

It is a type of variation in which one variable varies directly to the product of two or more variables

When direct and inverse variations happen at the same time.

It is a relationship between two quantities, x and y, where, as x increases y also increases or as y decreases, x also decreases and the ratio between them is constant or the same for all given values of the variables.

It is the relationships between variables that are represented in the form of y = k/x.

PROBLEM SOLVING:

The amount of paint (p) needed to paint the walls of a room varies directly as the area (A) of the wall. If 2 gallons of paint is needed to paint a 40 m² wall, how many gallons of paint are needed to paint a wall with an area of 100 m²?

Answer: ___ gallons