__Parallelogram Law of Forces:__

It states that “**If two forces are acting simultaneously on a particle, be represented in magnitude and direction by the two adjacent sides of a parallelogram, their results may be represented in magnitude and direction by the diagonal of the parallelogram which passes through their point of intersection**“.

Mathematically, the resultant force,

Where, F_{1} and F_{2} = Forces whose resultant is required to be found out.

θ = Angle between the forces F_{1} and F_{2}

α = Angle which the resultant force makes with one of the forces say F_{1}.