Question

27х + 277у = 85.8
(0,5х + 0,5у)*102 = 91,5


как это решать , как выразить икс или игрик ? 

Answer 1

$1) \: 27x = - 277y + 85.8 \\ \frac{27x}{27} = - \frac{227y}{27} + \frac{85.8}{27} \\ x = - \frac{227}{27} + \frac{85.8}{27} \\ x = - \frac{227y}{27} + 3.17$
$2) \: 277y = - 27x + 85.8 \\ \frac{277y}{277} = - \frac{27x}{277} + \frac{85.8}{277} \\ y = - \frac{27x}{277} + \frac{85.8}{277} \\ y = - \frac{27x}{277} + 0.3$
$3) \: 0.5x \times 102 + 0.5x \times 102 = 91.5 \\ 51x + 51y = 91.5 \\ 51x = - 51y + 91.5 \\ \frac{51x}{51} = - \frac{51y}{51} + \frac{91.5}{51} \\ x = - \frac{51y}{51} + \frac{91.5}{51} \\ x = - y + \frac{91.5}{51} \\ x = - y + 1.8$
$4) \: 0.5x \times 102 + 0.5y \times 102 = 91.5 \\ 51x + 51y = 91.5 \\ 51y = - 51x + 91.5 \\ \frac{51y}{51} = - \frac{51x}{51} + \frac{91.5}{51} \\ y = - \frac{51x}{51} + \frac{91.5}{51} \\ y = - x + 1.8$