Answer:
1398.12 N
Step-by-step explanation:
We define the x-axis in the direction parallel to the movement of the truck on and the y-axis in the direction perpendicular to it.
x-components of the ropes forces
T₁x = 615N*cos31°=527.1579 N :Tension in direction x of the rope of the car 1
T₂x= 961 N*cos25°=870.96 N :Tension in direction x of the rope of the car 2
Net forward force exerted on the truck in the direction it is headed (Fnx)
Fnx = T₁x + T₂x
Fnx = 527.1579 N + 870.96 N
Fnx = 1398.12 N