Un herrero fabrica aleaciones utilizando como base tres minerales: plata, hierro y cobre. se conoce que cada kilogramo de plata, hierro, y cobre cuestan respectivamente 10, 4 y 2 monedas de oro. el herrero requiere 11 kilogramos de una aleaci ́on, cuyo costo en materiales sea de 40 monedas de oro, y adem ́as, para garantizar su efectividad es necesario que la cantidad de hierro sea el doble de la cantidad de cobre. ¿qu ́e cantidad de cobre es necesaria para elaborar la aleaci ́on?

3.5 kg de cobre

Step-by-step explanation:

peso de plata = p

peso de hierro = h

peso de cobre = c

Peso:

peso total: p + h + c = 11

Valor:

10p + 4h + 2c = 40

5p + 2h + c = 20

Regla:

h = 2c

Sistema de equaciones:

p + h + c = 11

5p + 2h + c = 20

h = 2c

p + 2c + c = 11

p + 3c = 11

5p + 2(2c) + c = 20

5p + 5c = 20

-5p - 15c = -55

5p + 5c = 20

-10c = -35

c = 3.5    cobre

h = 2c = 2(3.5) = 7     hierro

p + 3c = 11

p = -3(3.5) + 11

p = 0.5     plata

answer: 2 answers

step-by-step explanation: the first one means to spread the product throughout the marketplace such that a large number of people can buy it.  

the second means the process of making a product or service available for the consumer or business user that needs it.

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