# Finding the x-intercept

1. Mar 11, 2010

### MrNeWBiE

1. The problem statement, all variables and given/known data

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):

3. 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

2. Mar 11, 2010

### benhou

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.

3. Mar 11, 2010

### MrNeWBiE

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

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

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

4. Mar 11, 2010

### benhou

Looks good to me!

5. Mar 11, 2010

### MrNeWBiE

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