Question 353768
Let P be the point (p,q) and L the line y = m x + b. It is not necessary, but if you like you may assume that P lies below the line L. All your answers below should be algebraic expressions in terms of m, b, p and q. The slope of L is ____. 
The slope of a line perpendicular to L is m__. 
The line through P perpendicular to L can be written as y = s x + c 
where s is:-1/m___ and c is:(mq+p)/m___ . 
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That line intersects L in the point Q = (u,v), 
where u is: (mq+q-cm)/(m^2+1)___ 
and v is:[m^2q +mp+c]/[m^2+1)___. 
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I'll leave the rest to you.
Cheers,
Stan H.
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The distance of P and Q is ____. The expression you enter here may be quite messy. However, if it is correct it can be simplified into a very concise and meaningful form. Make sure you check the solution of this problem when the set closes.
Hint: If you are bewildered by all the symbols ask yourself what they mean in the special case of the preceding problem, and compare your calculations for this problem with the numerical calculations you did earlier. 
So here are the answers that I have so far. 
1. m
2. -1/m
3. -1/m
4. ?
5. ?
6. ?
7. ?