Resposta:
a) [tex]16[/tex]
b) [tex]7\sqrt{2}[/tex]
c) [tex]10\sqrt{3}[/tex]
d) [tex]12\sqrt{3}[/tex]
Explicação passo a passo:
a)
[tex]sen30=\frac{8}{x}\\\\\frac{1}{2} =\frac{8}{x}\\\\x=16[/tex]
b)
[tex]cos45=\frac{7}{x}\\\\\frac{\sqrt{2}}{2}=\frac{7}{x}\\\\\sqrt{2}x=14\\\\x=\frac{14}{\sqrt{2}}\times\frac{\sqrt{2}}{\sqrt{2}}\\\\x=\frac{14\sqrt{2} }{2}\\\\x=7\sqrt{2}[/tex]
c)
[tex]cos30=\frac{x}{20}\\\\\frac{\sqrt{3} }{2} =\frac{x}{20}\\\\2x=20\sqrt{3} \\\\x=\frac{20\sqrt{3} }{2}\\\\ x=10\sqrt{3}[/tex]
d)
[tex]tg60=\frac{x}{12}\\\\\sqrt{3} =\frac{x}{12} \\\\x=12\sqrt{3}[/tex]