Respuesta :

Answer: [tex]x=7 sqrt(6)\ \ or\ x=7\sqrt{6}[/tex]

Step-by-step explanation:

For this exercise you can use the following Trigonometric Identity:

[tex]sin\alpha =\frac{opposite}{hypotenuse}[/tex]

In this case you can identify in the figure given in the exercise that:

[tex]\alpha =45\°\\\\opposite=7\sqrt{3}\\\\hypotenuse=x[/tex]

Knowing those values, you must substitute them into  [tex]sin\alpha =\frac{opposite}{hypotenuse}[/tex], as following:

[tex]sin(45\°)=\frac{7\sqrt{3}}{x}[/tex]

Now you must solve for "x" in order to find its value.

You need to remember that, by definition:

 [tex]sin(45\°)=\frac{1}{\sqrt{2}}[/tex]

Therefore, you get that the value of "x" is:

[tex](x)(\frac{1}{\sqrt{2}} )=7\sqrt{3}\\\\x=(7\sqrt{3})( \sqrt{2}})\\\\x=7\sqrt{6}}[/tex]