Question

Willa says the slope of the graph is -1/3.What error did she make?​

Answer 1

ANSWER

She counted the squares instead of using the scale.

EXPLANATION

The slope of a line is calculated using the formula

$m = \frac{rise}{run}$

This is the same as:

$m = \frac{y_2-y_1}{x_2-x_1}$

The given straight line passes through:

(4,24) and (16,18).

We plug in the values to obtain,

$m = \frac{18 - 24}{16 - 4}$

$m = \frac{ - 6}{12}$

$m = - \frac{ 1}{2}$

This is the correct expression for the slope.

But Willa mistakenly counted the squares instead of using the scale and had

$m = - \frac{1}{3}$

Each box on the y-axis is 3 units and each box on the x-axis is 2 units.

The rise is one box along the y-axis which is equal to 3 units the run is 3 boxes which is equal to 6 units.

The line has a negative slope.

Because she just counted the boxes and did use the scale, she got a wrong answer.

Answer 2

Answer:

She counted the squares instead of using the scale.

Step-by-step explanation:

I did the test