Answer
a) The resultant force is about 5600 N.
b) And its direction is along the dashed line between the two forces.
Work Step by Step
a)
We need to find one force that is equal to the resultant of the two forces exerted by the two ropes. And we need to find the magnitude and the direction of this force graphically as the author mentioned.
We know that the two forces exerted by the two ropes on the car are equal and the magnitude of each one of them is 2900 N. We also know that the angle between them is 30$^\circ$
The author also asked to arrange them head to tail in order to find the resultant force, as you see in the figure below.
We used a software calculator to find the direction and the magnitude graphically without doing any math.
From the figure below, we see that
a) The resultant force is about 5600 N.
b) And its direction is along the dashed line between the two forces.
Note that we used a scale of 1 cm to each 100 N.
