Show that the given points are the vertices of an isosceles triangle. Use the
distance formula. (Show that two sides of the triangle are equal in length).
1.) A (-1, -6), B (2, -7), C (-2, -3)
2.) A (-9, 3), B (-4, 8), C (0, -1)
3.) A (2, -3), B (3, 4), C (-5, -2)
4.) A (-3, 0), B (-6, 7), C (1, 4)
The question tells you exactly what to do.
You work out the distance between the vertices using the distance formula.
Once you have all three distances of the triangles, you should be able to see that in each triangle, two distances are equal. So the triangles are isosceles.
E.g. for the first one, you have
.
.
Now work out the distance of and .