Answer:
isosceles
Explanation:
The point B is located on the perpendicular bisector of AC. No calculation is necessary. AC has a slope of 1, so it is easy to count grid squares to see where the perpendicular bisector goes.
When the altitude of the triangle bisects the side opposite the vertex, it is an isosceles triangle.
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Apparently, you're to use the distance formula to determine the lengths of the sides of the triangle. Doing that, you would find ...
AB² = (6-4)² +(1 -6)² = 4 + 25
CB² = (6-1)² +(1-3)² = 25 + 4
At this point, it doesn't require much thought to realize these sides are the same length: √29.