Posted by **HongKit** on Wednesday, October 17, 2012 at 12:14pm.

A vector equation for a given straight line is r = (i + 3j) + lambda (-i - j)

Construct a vector equation for the line that does go through the point (1,2), and is perpendicular to r.

and

Determine the point of intersection of the two lines

- math -
**Steve**, Wednesday, October 17, 2012 at 3:18pm
you know that i-j is perpendicular to -i-j since (-1)(1) + (-1)(-1) = -1+1 = 0

so, i+2j + alpha(i - j) will do the trick

1-lambda = 1 + alpha

3-lambda = 2 - alpha

intersect where lambda = 1/2 alpha = -1/2, at the point (1/2,5/2)

## Answer this Question

## Related Questions

- Precalc - A line in space has the vector equation shown here. Fill in the blanks...
- Math/Vectors - I need help on a homework problem. "Determine a vector equation ...
- Discrete Math: Equations of Line in a Plane - I'm stuck on these questions. Can ...
- Math: Equations of Line in a Plane - I'm stuck on these questions. Can you ...
- Vectors - Determine the vector equation of a line passing through the point P(3,...
- Maths Vector Helpppp - The points A and B have position vectors, relative to the...
- Precalc - At the point were a line intersects a plane [with the equation (24x+...
- Calculus - 4. Write a vector equation of the line through the point (5, -2, 3) ...
- Calculus - 4. Write a vector equation of the line through the point (5, -2, 3) ...
- Calculus - 4. Write a vector equation of the line through the point (5, -2, 3) ...