Question

Erma and Kris are comparing two different linear functions. Erma’s function has the equation y = 3x – 2. The table lists several points on Kris’s function.

What fraction represents the difference, in units, between the x-intercepts of the functions?

Answer 1

4/3

Explanation:

We can try to find Kris's function first with the values provided in the table. We do this with the slope formula. (y2 - y1) / (x2 - x1)

(-1 + 1/2) / (0 - 1)

-0.5 / -1

The slope is -1/2. We can find the y-intercept when x equals 0. It is already in the table, so we now have Kris's function.

y = -1/2 - 1

y = 3x - 2

We find the x-intercept when y = 0 on the function. For Kris's function, its also provided already, which is 2.

For Erma's function, we make y = 0

0 = 3x - 2

2 = 3x

2/3 = x

To find the difference, we subtract the smaller one from the greater one.

2 - 2/3 = 4/3

This fraction represents the difference.