DIRECT, INVERSE, JOINT AND COMBINED VARIATIONS

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

If y varies directly as x and y = 39 when x = 3, what is the value of y when x = 2?

Back

y = 26

Front

What is inverse variation?

Back

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

Front

If the frequency of a vibrating string varies inversely as its length, and a 3-foot string vibrates 175 cycles per second, what is the frequency of a 5-foot string?

Back

Frequency = 105 cycles

Front

What is joint variation?

Back

Joint variation is a relationship where a variable varies directly with two or more other variables. It can be expressed as y = kxz, where k is a non-zero constant.

Front

What does the equation w = 10chs represent?

Back

The equation represents joint variation.

Front

If y varies inversely with x and y = 150 when x = 2, what is y when x = 25?

Back

y = 12

Front

How do you find the constant of variation in direct variation?

Back

To find the constant of variation (k), divide y by x (k = y/x) when given a pair of values.

Front

How do you find the constant of variation in inverse variation?

Back

To find the constant of variation (k), multiply y by x (k = xy) when given a pair of values.

Front

If y varies directly as x and y = 22.5 when x = 15, what is y when x = 20?

Back

y = 30