# Finding the x-intercept

MrNeWBiE

## Homework Statement

Find the x-intercept of the line that passes through the point (1; 2) and perpendicular to the
line joining (1; 1) and (3; 4):

## The Attempt at a Solution

I want to confirm my steps if it's right ,,,,

M=(4-1)/(3-1)= 3/2

y-1=3/2(x-1) ====> y=(3/2)x-1/2

perpendicular = m1xm2=-1 ====> m2=-2/3

y-2=-2/3(x-1) ====> y=(-2/3)x+4/5

making it one equation

(3/2)x-(1/2)=(2/3)x+(4/3)
x=11/13

benhou
making it one equation

(3/2)x-(1/2)=(2/3)x+(4/3)
x=11/13

I am not sure what you did here. I am assuming you were trying to combine the equation of the first line with the second line. If so, you have calculated the point of intersection of the two lines, which is not what the question has asked for. The question asked you for the x-intercept of the line.

MrNeWBiE
aha ,,,
so I should not combine them ,,,

(-2/3)x+4/5 = 0 ?

and the answer will be (10/13,0)

benhou
Looks good to me!

MrNeWBiE
ops ,,,
I had a mistake in y=(-2/3)x+4/5 ,,, should be y=(-2/3)x+8/3