# Vector Magnitude problem

I do not understand how to set up the following problem:

"Forces of 20 lb and 32 lb make an angle of 52 degrees with each other. find the magnitude of the resultant force."

An actually picture would really help.

• So why don't you draw a picture? Have you learned about vector addition? – Jonas Meyer Apr 25 '15 at 22:29

In the diagram, your vectors are $OD$ of length $20$ and $OB$ of length $30$. To add the vectors, we "slide" a copy of $OD$ so it starts at $B$, giving us vector $BE$. We can use sine and cosine in the resulting right triangle $BEF$ to get its sides. You want vector $OE$, and you now know the sides: $EF$ which you already found, and $OF$ which equals $OB+BF$.
You can now use the Pythagorean theorem to find the length of $OE$, which is your answer.