Krystina is trying to derive the slope of a line with coordinates (6,−2)

Question

and (0,8)
using the formula ΔyΔx=y2−y1x2−x1
.

Krystina says the slope is −35
because slope =riserun=x2−x1y2−y1=0−68−(−2)=−68+2=−610
.

Is Krystina’s calculation for slope correct? If not, what is an appropriate explanation for why she is incorrect?

Krystina is correct and she simplified the slope correctly.

Krystina is correct because she calculated the change in x over the change in y.

Krystina is incorrect because she calculated the change in y over the change in x.

Krystina is incorrect because she calculated the change in x over the change in y.

Answer 1

Krystina's calculation for the slope is incorrect because she calculated the change in x over the change in y instead of the change in y over the change in x. The correct calculation would be Δy/Δx = (y2 - y1)/(x2 - x1) = (8 - (-2))/(0 - 6) = 10/-6 = -5/3.