Write an equation for the following statements: 1. The fare \( F \) of a passenger varies directly as the distance \( d \) of his destination. 2. The cost \( C \) of fish varies directly as its weight \( w \) in kilograms. 3. An employee's salary \( S \) varies directly as the number of days \( d \) he has worked. 4. The area \( A \) of a square varies directly as the square of its side \( s \). 5. The distance \( D \) travelled by a car varies directly as its speed \( s \).

sueldo mensual de un vendedor de una marca de celulares se compone de monto fijo de \( \$ 400000 \) más una comisión de \( \$ 5000 \) por cada celular que nde en el mes. zué función permite obtener el sueldo \( S(n) \) del vendedor, en pesos, cuand nde \( n \) celulares en un mes? (A) \( S(n)=400000+\frac{5000}{n} \) (B) \( S(n)=400000+5000 \cdot n \) (C) \( S(n)=400000 \cdot n+5000 \) (D) \( S(n)=\frac{400000}{n}+5000 \)

а) \( \left\{\begin{array}{ll}4(x-y)=-2, \\ 3 x-7 y=-2,5-2(x+y) ;\end{array}\right. \) в) \( \left\{\begin{array}{l}3(x+y)=6, \\ 6+5(x-y)=8 x-2 y ; \\ 14-3(x+y)=8,\end{array}\right. \) \( 14-5 y-x ; \) г) \( \left\{\begin{array}{l}5(x-y)=10, \\ 3 x-7 y=20-(x+3 y) .\end{array}\right. \).

5) \( \left(\frac{1}{3}\right)^{x}=3 \)

2) \( x^{2}-8 x+12=0 \)

14) Classifique o sistema a seguir em possível e determinado, possível e indeterminado ou impòssível. \( \left\{\begin{array}{l}3 x+4 y=12 \\ x+y=5\end{array}\right. \)