A line segment is bisected by a line with the equation 4 y - 3 x = 2 . If one end of the line segment is at ( 2 , 1 ), where is the other end?

1 Answer
Jan 24, 2017

(1 1/25,2 7/25)

Explanation:

4y-3x=2, 4y=3x+2
y=3/4x+1/2 ->a

gradient of the other line, m = -1/(3/4)=-4/3

The equation of the line thru (2,1),

y-y_1=m(x-x_1)
y-1=-4/3(x-2)
y=-4/3x+8/3+1
y=-4/3x+11/3

replacing y from a

3/4x+1/2=-4/3x+11/3

3/4x+4/3x=11/3-1/2

9/12x+16/12x=22/6-3/6

25/12x=19/6

x=19/6*12/25=38/25

y=3/4(38/25)+1/2

y=57/50+25/50=82/50=41/25

(38/25,41/25) is a midpoint of the line.

The other end of the line, (x,y).

(x+2)/2=38/25
x=38/25*2-2
x=76/25-50/25=26/25=1 1/25

(y+1)/2=41/25
y=41/25*2-1
y=82/25-25/25=57/25=2 7/25

The other end (1 1/25,2 7/25)