Subtracting two vectors -- I'm not getting the right answer

[Aleksa]

Homework Statement

I have vector a=3 that is horizontal and vector b=3 with an angle of 120. They have same direction. I need to find c=b-a.

Relevant Equations

Pythagorean theorem

I added x and y-axis so it would be square, and then vector bx would be same as vector a, but a didn't get it right. I am out of ideas. Can you help me?

 

[PeroK]

I'm not sure I understand your question. Could you post a diagram of your vectors $\vec a$ and $\vec b$ and your attempt to find $\vec c$?

 

[berkeman]

Homework Statement:: I have vector a=3 that is horizontal and vector b=3 with an angle of 120. They have same direction. I need to find c=b-a.
Relevant Equations:: Pythagorean theorem

I added x and y-axis so it would be square, and then vector bx would be same as vector a, but a didn't get it right. I am out of ideas. Can you help me?

Welcome to PF.

What are the x and y components of each vector? What do you get when you do the vector subtraction component-wise? Please show your work. Thanks.