170k views
20 votes
Write an equation of the perpendicular bisector of the segment with the endpoints (-8,-1) and (4,5)

1 Answer

8 votes

9514 1404 393

Answer:

2x +y = -2

Explanation:

The bisector must have a slope that is the negative reciprocal of the slope of the line between these points. It must pass through the midpoint of the segment.

The slope of the line through the given points is ...

m = (y2 -y1)/(x2 -x1)

= (5 -(-1))/(4 -(-8)) = 6/12 = 1/2

The slope of the required bisector is then ...

m = -1/(1/2) = -2

__

The midpoint of the given segment is ...

((-8, -1) +(4, 5))/2 = (-8+4, -1+5)/2 = (-4, 4)/2 = (-2, 2)

__

Then the point-slope form of the equation of the bisector is ...

y -y1 = m(x -x1)

y -2 = -2(x -(-2))

y = -2x -4 +2

y = -2x -2 . . . . . . . slope-intercept form equation

2x +y = -2 . . . . . . . standard form equation

Write an equation of the perpendicular bisector of the segment with the endpoints-example-1
User Cjames
by
4.4k points