Find the length of side x in simplest radical form with a rational denominator.
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Answer:
x = 5[tex]\sqrt{2}[/tex]
Step-by-step explanation:
Using the cosine ratio in the right triangle and the exact value
cos45° = [tex]\frac{1}{\sqrt{2} }[/tex] , then
cos45° = [tex]\frac{adjacent}{hypotenuse}[/tex] = [tex]\frac{5}{x}[/tex] = [tex]\frac{1}{\sqrt{2} }[/tex] ( cross- multiply )
x = 5[tex]\sqrt{2}[/tex]