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Bernice · #1 June 27th, 2009, 03:38 PM

I have always had problems with vectors and now need help to understend this simpe task:

Given triangle ABC with vertices A(-2; 5), B(-5; 4), C(1;1).

Find:
1)vecto $\overrightarrow{AB} \ \overrightarrow{CB}\ \overrightarrow{CA}$ coordinates and length

2) internal angle to vertice B

3) general equation of line AB

4) general equation of height CD

5)edge AB and height CD intersection D

For 1st I think that $\overrightarrow{AB}=\sqrt{(-5+2)^2+(4-5)^2}=\sqrt{10}$

$\overrightarrow{CB}=\sqrt{(-5-1)^2+(4-1)^2}=\sqrt{45}$

$\overrightarrow{CA}=\sqrt {(-2-1)^2+(-1)^2}=5$