you can use the Pythagorean theorem to solve this
[tex]{x}^{2} = {4}^{2} + {2}^{2} [/tex]
Now solve for x
[tex] {x}^{2} = 16 + 4 \\ {x}^{2} = 20 \\ x = \sqrt{20} [/tex]
Now you can simplify this to
[tex]x = \sqrt{5 \times 4} \\ x = \sqrt{5} \sqrt{4} \\ x = \sqrt{5 } \times 2 \\ x = 2 \sqrt{5} [/tex]
And that's your answer
