precalculus
posted by kennedy on .
write an equation in general form...
the perpendicular bisector of the segment with endpoints at (2,1) and (4,5). I found the slope and then found the mid point and wrote to the equation and got X2Y=3. But the answer is X2Y=9...any help???

slope is of the segment is 2, you got that correct, and slope of bisector is 1/2, right. The midpoint is at 3,3
y=mx+b
3=3/2 + b
b= 4.5
y=1/2 x 4.5
2y=x9
x2y=9 
The mid point of the segment is
((x1+x2)/2, (y1+y2)/2)=(3,3)
You have correctly calculated the slope m as 1/2.
Using the equation
(yy1)=m(xx1),
we get
(y(3))=(1/2)(x3)
2(y+3)=x3
x2y=9
You have probably miscalculated the midpoint as (3,3)