A line segment is bisected by a line with the equation 7 y + x = 7 . If one end of the line segment is at (1 ,3 ), where is the other end?

1 Answer
Jul 9, 2017

The other end is =(0.4,-1.2)

Explanation:

Let's rewrite the equation of the line.

7y+x=7

7y=-x+7

y=-1/7x+1................................(1)

The slope is m=-1/7

The slope of the perpendicular line is m'=-1/m=-1/(-1/7)=7

The equation of the perpendicular line is

y-3=7(x-1)

y=7x-7+3=7x-4.......................(2)

The point of intersection is obtained by solving for x and y in equations (1) and (2)

7x-4=-1/7x+1

7x+1/7x=4+1=5

50/7x=5

x=5*7/50=7/10=0.7

y=7*0.7-4=4.9-0.4=0.9

The point of intersection is =(0.7,0.9)

Let the other end of the line segment be =(a,b)

Then,

((a+1)/2,(b+3)/2)=(0.7,0.9)

a+1=2*0.7=1.4, => , a=1.4-1=0.4

b+3=2*0.9=1.8, =>, b=1.8-3=-1.2

The other end is =(0.4,-1.2)