Review of: Slope and Direct Variation

Front

What is the average rate of change?

Back

The average rate of change is the change in the value of a quantity divided by the change in time. It represents how much a quantity changes on average over a specific interval.

Front

What is the formula for direct variation?

Back

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

Front

Is the equation y = 2x a direct variation?

Back

Yes, because it can be expressed in the form y = kx, where k = 2.

Front

What does it mean if y varies directly with x?

Back

It means that as x increases or decreases, y increases or decreases proportionally.

Front

How do you find the slope of a line?

Back

The slope (m) is found using the formula m = (y2 - y1) / (x2 - x1), where (x1, y1) and (x2, y2) are two points on the line.

Front

What is the slope of a horizontal line?

Back

The slope of a horizontal line is 0.

Front

If y = 84 when x = 16, what is the constant of proportionality (k)?

Back

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

Front

What is the meaning of 'constant of proportionality'?

Back

The constant of proportionality is the constant factor (k) that relates two variables in a direct variation.

Front

If $70 is earned in 5 hours, how much is earned in 22 hours?

Back

$308, calculated using the ratio of earnings to hours worked.

Front

What is the slope of a vertical line?

Back

The slope of a vertical line is undefined.