Question

Which number line can be used to find the distance between (4, -1) and (8, -1)? 23 5 78 + -2 -1 0 1 2 3 5 6 7 8 -2 -1 0 1 2 3 4 5 6 7 8 -7 -6 -5 -4 -3 -2 -1 0 1

Answer 1

Given the points:

(x1, y1) ==> (4, -1)

(x2, y2) ==> (8, -1)

Here, we have the same values of y for both points.

This means that the line that contains both points is a horizontal line.

To find the distance, apply the formula:

$d=\sqrt[]{(x2-x1)^2+(y2-y1)^2}$

Since they have the same y values, the number line to represent the distance between both points must have the points 4 and 8.

Thus, we have:

$\begin{gathered} d=\sqrt[]{(8-4)^2+(-1-(-1))^2} \\ \\ d=\sqrt[]{4^2+0^2} \\ \\ d=\sqrt[]{16} \\ \\ d=4 \end{gathered}$

The distance between both points is 4

Therefore, the number line that can be used to find the distance between both points is the number line in option A.

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