Question

Two concurrent forces of 12 newton and 18 newton and acting at an angle of 60 degree find the resultant force taking p = 12 newton and q = 18 newton

Answer 1

duiofxcalico ignoring supposedly distinct

Answer 2

Considering the angle given as the angle between P and Q
Now
$r = \sqrt[]{p {}^{2} + q {}^{2} + 2pq\cos( \alpha ) }$
$= \sqrt{12 {}^{2} + 18 {}^{2} + 2pq \cos(60) }$
$= \sqrt[]{144 + 324 + 2 \times 12 \times 18 \cos(60) }$
=√684
=26.15 N
Hope it helps
:)