This can be solved a couple of ways. One way is to use the Pythagorean theorem to write equations for the magnitude from the components of the forces. That is what was done in the graph here.
Another way is to use the Law of Cosines, which lets you make direct use of the angle between the vectors.
.. 13 = a^2 +b^2 -2ab*cos(90°)
.. 19 = a^2 +b^2 -2ab*cos(120°)
Subtracting the first equation from the second, we have
.. 6 = -2ab*cos(120°)
.. ab = 6
Substituting this into the first equation, we have
.. 13 = a^2 +(6/a)^2
.. a^4 -13a^2 +36 = 0
.. (a^2 -9)(a^2 -4) = 0
.. a = ±3 or ±2
The magnitudes of the two forces are 2N and 3N, in no particular order.
Answer: 41.58$
Step-by-step explanation:
The answer is B. <span>Two lines are perpendicular if they meet at one point and one of the angles at their point of intersection is a right angle. A perpendicular line has to intersect and have a 90-degree angle in order to be perpendicular.</span>
For this case, we must find an expression equivalent to:

By definition of power properties we have:

Rewriting the previous expression we have:
The "-" are canceled and we take into account that:

So:

According to one of the properties of powers of the same base, we must put the same base and add the exponents:

Answer:

Option B