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. It can be expressed as y = kx, where k is a non-zero constant.

Front

What does the equation y = kx represent?

Back

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

Front

If y = 39 when x = 3, what is the constant of variation (k)?

Back

k = y/x = 39/3 = 13.

Front

If y varies directly with x and y = 84 when x = 16, what is the value of k?

Back

k = y/x = 84/16 = 5.25.

Front

How do you find y when x is given in a direct variation?

Back

To find y, use the equation y = kx, substituting the value of k and the given x.

Front

If $70 is earned in 5 hours, how much is earned in 1 hour?

Back

Earnings per hour = $70/5 = $14.

Front

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

Back

k = y/x = 4/(-4) = -1.

Front

What is the formula to find y when x is known in direct variation?

Back

The formula is y = kx, where k is the constant of variation.

Front

If y = 5.25x, what is the value of y when x = 10?

Back

y = 5.25 * 10 = 52.5.

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.