Direct Variation

Front

What is Direct Variation?

Back

Direct Variation is a relationship between two variables where one variable is a constant multiple of the other, expressed as y = kx, where k is the constant of proportionality.

Front

What does the equation y = kx represent?

Back

The equation y = kx represents a direct variation, where y varies directly with x and k is the constant of proportionality.

Front

What is the constant of proportionality in the equation y = 7x?

Back

The constant of proportionality is 7.

Front

What is the graph of a direct variation?

Back

The graph of a direct variation is a straight line that passes through the origin.

Front

If y varies directly with x and y = 12 when x = 15, what is the constant of proportionality k?

Back

k = y/x = 12/15 = 0.8.

Front

How do you find the value of y when x is known in a direct variation?

Back

Use the equation y = kx, substituting the known value of x and the constant k.

Front

What is the relationship between x and y in direct variation?

Back

In direct variation, as x increases, y increases proportionally, and as x decreases, y decreases proportionally.

Front

What does it mean if two quantities are directly proportional?

Back

It means that the ratio of the two quantities remains constant.

Front

What is an example of a direct variation in real life?

Back

An example is the relationship between distance and time when traveling at a constant speed.

Front

If y = 4x, what is the value of y when x = 5?

Back

y = 4 * 5 = 20.