Calculate Resultant Force and Angle of Object at Origin

[zaga04]

Homework Statement

An object is at the origin. They're four perpendicular forces acting upon it. In the negative x axis, 18 N. positive x axis, 10 N. negative y axis, 8 N. and positive y-axis 15 N. calculate the resultant force. What angle is it at?

Homework Equations

F=Ma?

The Attempt at a Solution

Not really sure how to get the resultant force. Do you just add 8+10-15-18? (since 15 and 18 are negative)? For the angle, would it be 90 degrees?

 

[Jebus_Chris]

You add vectors/forces by adding their x components and their y components together.

 

[zaga04]

So would it just be 8+10-15-18 since they are at 90? They wouldn't have any x and y components since they are not at an angle. Also what would the resultant angle be?

 

[Jebus_Chris]

If a force of 10N is directed upwards on the y-axis it as a y compnent of 10N and an x component of 0N. Similarily if a force is directed to the right on the x-axis it has a y component of 0N and an x component of 10N.