Question

Metodo de igualacion

5x/12-y=9

x-3y/4=15

Answer 1

Respuesta:

$\frac{5x}{12} - y = 9 (1)\\ x - \frac{3y}{4} = 15(2) \\ \frac{5x}{12} = 9 + y \\ 5x = 12(9 + y) \\ 5x = 108 + 12y \\ x = \frac{108 + 12y}{5} (1)60 \\ x = 15 + \frac{3y}{4} (2) \\ igualamos \: 1 \: y \: 2 \\ \frac{108 + 12y}{5} = 15 + \frac{3y}{4} \\ \frac{108 + 12y}{5} = \frac{60 + 3y}{4} \\ 4(108 + 12y) = 5(60 + 3y) \\ 432 + 48y = 300 + 15y \\ 48y - 15y = 300 - 432 \\ 33y = - 132 \\ y = \frac{ - 132}{33} \\ y = - 4 \\ sustituimos y \\ x - \frac{3y}{4} = 15 \\ \times - \frac{3( - 4)}{4} = 15 \\ x - \frac{ - 12}{4} = 15 \\ x - ( - 3) = 15 \\ x + 3 = 15 \\ x = 15 - 3 \\ x = 12$