WAEC - Mathematics (2018 - No. 16)
If M and N are the points (-3, 8) and (5, -7) respectively, find |MN|
8 units
11 units
15 units
17 units
คำอธิบาย
|MN| = \(\sqrt{(x_1 - x_2)^2 + (y_1 - y_2)^2}\)
= \(\sqrt{(-3 -5)^2 + (8 - 7)^2}\)
= \(\sqrt{(-8)^2 + (8 + 7)^2}\)
= \(\sqrt{64 + (15)^2}\)
= \(\sqrt{64 + 225}\)
= \(\sqrt{289}\)
= 17 units