Resposta:
b = 69,23
c = 59,23
Explicação passo a passo:
Lei do seno
[tex]\dfrac{c}{sen~50^{\circ}}=\dfrac{b}{sen~64^{\circ}}=\dfrac{70}{sen~66^{\circ}}\\ \\ \\ \dfrac{c}{0,77}=\dfrac{b}{0,90}=\dfrac{70}{0,91}[/tex]
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[tex]\dfrac{b}{0,90}=\dfrac{70}{0,91}\\ \\ \\ b=\dfrac{0,90\times70}{0,91} = \dfrac{63}{0,91}\\ \\ \\\boxed{ b=69,23}\\ \\ \\ \dfrac{c}{0,77}=\dfrac{79}{0,91}\\ \\ \\ c=\dfrac{70\times0,77}{0,91}=\dfrac{53,9}{0,91}\\ \\ \\\boxed{ c=59,23}[/tex]
