You can
put this solution on YOUR website!Assuming by B(3,o) you meant (3,0)...
Distance is from

or
But, that means you need to know the a and the b. If you plotted this triangle, you'd see that AB = AC, as A is centered on the x-axis between B and C, and B and C are at the same y-value.
So, let's start with the easy one, BC = 6, since it is from -3 to 3.
So, you can either do AB or AC, I chose AB, for no real reason.
So, a and b, from the equation above are the x distance and y distance.
So, x-distance is (3-0) = 3
y-distance =

=
So the side are 6,6,6 which is an equilateral triangle.