SOLUTION: Two perpendicular lines have the same x-intercept. An equation of one line is y=3x+1. Find an equation of the other line.

Algebra ->  Linear-equations -> SOLUTION: Two perpendicular lines have the same x-intercept. An equation of one line is y=3x+1. Find an equation of the other line.      Log On


   

Question 882301: Two perpendicular lines have the same x-intercept. An equation of one line is y=3x+1. Find an equation of the other line.
Found 2 solutions by josgarithmetic, MathTherapy:
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Same x-intercept. Find that value using the given line.
y=3x%2B1
3x%2B1=y=0
3x%2B1=0
3x=-1
x=-1%2F3, so point is (-1/3, 0).

The other line, perpendicular, is y=-%281%2F3%29x%2Bb, NOT because of the x-intercept; but because you need 3*m=-1, the product of the slopes must be negative 1. Now you still need to solve for b.
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b=y-%28-1%2F3%29x
Substitute the known point which is on both lines.
b=0-%28-1%2F3%29%28-1%2F3%29
b=1%2F9
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Wanted Equation: highlight%28y=-%281%2F3%29x%2B1%2F9%29.

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!

Two perpendicular lines have the same x-intercept. An equation of one line is y=3x+1. Find an equation of the other line.


Equation of other line: highlight_green%28highlight_green%28y+=+-+%281%2F3%29x+-+1%2F9%29%29