Question 982117
The other vertex that forms the triangle is on a line perpendicular to the segment at its midpoint.
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Find the midpoint:
midpoint=((x1+x2)/2,((y1+y2)/2)
midpoint=((-5+2)/2,(3+3)/2)
midpoint=(-(3/2),3)
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Find the slope of the original segment:
m=slope
m=(y2-y1)/x2-x1
m=(3-3)/(2-(-5)=0/7=0
The line is horizontal.
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The perpendicular line will be vertical, thus will have an undefined slope.
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Equation for original line:
y=mx+b
y=3
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The vertical line through the midpoint is x=-(3/2)

Any point on the line x=-(3/2) except (-(3/2),3) can be connected to the given vertices to form an isosceles triangle.