Find the length of side x in simplest radical form with a rational denominator.

Answer:
x = 2[tex]\sqrt{2}[/tex]
Step-by-step explanation:
Using the sine or cosine ratio in the right triangle and the exact value
cos45° = [tex]\frac{\sqrt{2} }{2}[/tex] , then
cos45° = [tex]\frac{adjacent}{hypotenuse}[/tex] = [tex]\frac{x}{4}[/tex] = [tex]\frac{\sqrt{2} }{2}[/tex] ( cross- multiply )
2x = 4[tex]\sqrt{2}[/tex] ( divide both sides by 2 )
x = 2[tex]\sqrt{2}[/tex]