Question

8. The distance between (3,5) and (9, -3) is:
A. 100
B. 2137
C. 2135
D. 10

Answer 1

10 (Answer D)

Explanation:

Here we see that the x-coordinate changes by 6, from 3 to 9, and that the y coordinate changes by 8, from 5 to -3.

We use the Pythagorean Theorem to calculate the distance between these two points. One leg of a triangle here has length 6 and the other leg has length 8. Applying this Theorem, we get:

6^2 + 8^2 = [ distance between (3, 5) and (9, -3) ]^2 = d^2, and so:

d^2 = 36 + 64 = 100.

This distance must be positive. Thus we take the positive square root of 100, which is 10. 10 is the distance between these two points.