Given A (-3,1) to origin to C (1,3). How do you measure that angle?

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Answer 1 · 2016-08-16T16:47:57

$m/_AOC=pi/2$ .

$A(-3,1), C(1,3)$ are given pts. and we require the measure of

$/_AOC$ , i.e., $m/_AOC$ , where, $O$ is the Origin, $O(0,0)$

Let the slope of line $OA$ be $m_1$ , and, $m_2$ that of line $OC$ .

Then, $m_1=(1-0)/(-3-0)=-1/3, and, m_2=(3-0)/(1-0)=3$ .

Hence, $m_1*m_2=(-1/3)(3)=-1$

$rArr OA bot OC$

$m/_AOC=pi/2$ .