Question 1

A)Stephen is trying to find the slope of a line that goes through the coordinates (8,-6) and (0,8) using the formula ΔyΔx=y2−y1x2−x1
. Stephen says the slope should be calculated as 0−88−(−6) = −47
. Is his calculation for slope correct? If not, why?(1 point)
Responses

Stephen is correct.
Stephen is correct.

Stephen is incorrect because he calculated the change in x over the change in y.
Stephen is incorrect because he calculated the change in x over the change in y.

Stephen is incorrect because he added instead of subtracted.
Stephen is incorrect because he added instead of subtracted.

Stephen is incorrect because he didn't simplify correctly.

1 answer

To determine if Stephen's calculation for the slope is correct, let's use the formula for the slope, which is given by:

\[ m = \frac{\Delta y}{\Delta x} = \frac{y_2 - y_1}{x_2 - x_1} \]

Using the coordinates (8, -6) as \((x_1, y_1)\) and (0, 8) as \((x_2, y_2)\):

  • \(x_1 = 8\)
  • \(y_1 = -6\)
  • \(x_2 = 0\)
  • \(y_2 = 8\)

Now, substituting these values into the slope formula:

\[ m = \frac{8 - (-6)}{0 - 8} = \frac{8 + 6}{0 - 8} = \frac{14}{-8} = -\frac{7}{4} \]

Stephen's calculation was incorrect, as he stated the slope to be \(-47\) and did not properly calculate the differences.

The correct reason for Stephen's incorrect answer is that he miscalculated the changes in y and x (adding instead of subtracting). Thus, the appropriate response is:

Stephen is incorrect because he added instead of subtracted.