# Show that the following points form a right angled triangle. (2, - 3), ( - 6, - 7) and ( - 8, - 3)

1

2014-05-22T11:18:20+05:30
TO start, you gotta find the slopes of each of these coordinates

You will end up with 3 slopes total:
1. Find the slope of the first two coordinates
(-2, 1) (3, 11)
m = (11 - (1)) / (3 - (-2))
= 10 / 5
= 2

2. Find the slope of the second and third coordinate:
(3, 11) (7, 9)
m = (9 - 11) / (7 - 3)
= -2/4
= -1/2

3. Find the slope of the first and third coordinates:
(-2, 1) (7, 9)
m = (9 - 1) / (7 - (-2))
m = 8 / 9

Now we got m = 2, -1/2, and 8/9

Since a right triangle has one 90 degree angle, we try to find two out of the three that are perpendicular to each other.
IN order to find that
when multiplied the two together you should get -1. (negative reciprocal)
m1 * m2 = -1

Try 2 and -1/2
2 * (-1/2)
= -1

Yes! We have two slopes of two segments that form a 90degree angle since 2 and -1/2 multiply to be -1 :D

So yes, they form a right triangle

hoep this helps :D