how can I find the third vertex? :(
The vertices of the base of an isosceles triangle are (-1,-2) and (1,4) . if the third vertex lies on the line 4x+3y-12=0, find the area of the triangle.

Question

how can I find the third vertex? :(
The vertices of the base of an isosceles triangle are (-1,-2) and (1,4) . if the third vertex lies on the line 4x+3y-12=0, find the area of the triangle.

anonymous · Answer

Because it's an isosceles triangle, the two side angles and legs are the same size, so the midpoint of the two vertices is the midpoint of the x values, which would be 0. Now you just evaluate the equation at x=0, making y=4. So the third vertex would be at (0, 4).

dumbcow · Answer

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the intersection between midline and given line 4x+3y-12=0 is the point of 3rd vertex