Question

May you please and give me the answer, im been stuck on it for 1 1/2 hours

Answer 1

Lets draw a picture of the problem:

The magnitude of the sum will the the magnitude of the red vector. Since we have a right triangle, we can apply Pytagorean theorem, that is,

`\begin{gathered} c^2=2^2+4^2 \\ c^2=4+16 \\ c^2=20 \end{gathered}`

Then, by applying square root to both sides, we have

`\begin{gathered} c=\sqrt[]{20} \\ c=\sqrt[]{4*5} \\ c=\sqrt[]{4}*\sqrt[]{5} \end{gathered}`

Therefore, the answer is

`c=2\sqrt[]{5}`

which correspondst to option 3 from left to right.