# Analytic Geometry Q4

• Jan 30th 2009, 11:09 PM
looi76
Analytic Geometry Q4
Question:
Find the slope of the line passing through $(4,5)$ and $(-8,-3)$ and find the angle of inclination of the line to the nearest degree.

Attempt:
$(4,5)$ $(-8,-3)$

$m = \frac{y_2 - y_1}{x_2 - x_1} = \frac{-3-5}{-8-4} = \frac{-8}{-12} = \frac{2}{3}$

$\phi = \tan^{-1}(m)$

$\phi = \tan^{-1}\left(\frac{2}{3}\right)$

$\phi = 33.7^o$

The nearest degree of the angle is $\phi = 34^o$