Direct & Inverse Variation Review

Front

What is direct variation?

Back

Direct variation is a relationship between two variables where one variable is a constant multiple of the other. It can be expressed as y = kx, where k is a non-zero constant.

Front

What is inverse variation?

Back

Inverse variation is a relationship between two variables where the product of the two variables is constant. It can be expressed as y = k/x, where k is a non-zero constant.

Front

If y varies directly as x and y = 12 when x = 4, what is y when x = 10?

Back

y = 30

Front

If y varies inversely as x and y = 5 when x = 3, what is y when x = 6?

Back

y = 2.5

Front

What is the constant of variation in direct variation?

Back

The constant of variation in direct variation is the constant k in the equation y = kx.

Front

What is the constant of variation in inverse variation?

Back

The constant of variation in inverse variation is the constant k in the equation y = k/x.

Front

If y varies directly as x and y = 20 when x = 5, what is the value of k?

Back

k = 4.

Front

If y varies inversely as x and k = 12, what is y when x = 4?

Back

y = 3.

Front

How do you determine if a relationship is a direct variation?

Back

A relationship is a direct variation if the ratio of y to x is constant.

Front

How do you determine if a relationship is an inverse variation?

Back

A relationship is an inverse variation if the product of x and y is constant.