Question

A taut clothesline extends between the points (–4.2, –6.4, 4.5) and (7.1, 2.2, 5.8), where the coordinates are in units of feet. What is the length of the clothesline?

Answer 1

17.54 ft

Explanation:

Moving along the line from (–4.2, –6.4, 4.5) to (7.1, 2.2, 5.8), x increases by 11.3, y by 8.6 and z by 10.3.

Applying the Pythagorean Theorem twice, we get

(length of clothesline) = √( 11.3² + 8.6² + 10.3²), or 17.54 ft.