You are given a vector in the xy plane that has a magnitude of 70.0 units and a y component of -55.0 units. What are the two possibilites for its x component? Please explain, thanks! :)

Answer 1

x^2=70^2-55^2

x= +- sqrt above.

Answer 2

Thanks so much! I should have thought of the pythagorean therom, but why x^2=70^2-55^2 rather than x^2+(-55^2)=70^2?

Answer 3

They both are the same thing. Solve for x^2 in your equation...