Question

Find the third vertex of an equilateral triangle if the other vertices are (-4,-1) and (4,3) ?

Answer 1

If you plot the two points then find the mid point between the two (-4+4/2 and -1+3/2) so the vertex is on the line crossing this point (0,1) i.e. y axis since x=0 also if you open compass as big as the distance between the two original points but put it on one of the points. The circle meets the midpoint line in two points so there are two answers.