Question

помогите, пожалуйста​

Answer 1

$\frac{x + y}{8} + \frac{x - y}{6} = 5 \: | \times 24\\ \frac{x + y}{4} + \frac{x - y}{5} = 10 \: | \times 20 \\ \\ \frac{24(x + y)}{8} + \frac{24(x - y)}{6} = 120 \\ \frac{20( x+ y)}{4} + \frac{20(x - y)}{5} = 200 \\ \\ 3(x + y) + 4(x - y) = 120 \\ 5(x + y) + 4(x - y) = 200 \\ \\ 3x + 3y + 4x - 4y = 120 \\ 5x + 5y + 4x - 4y = 200 \\ \\ 7x - y = 120 \\ 9x + y = 200 \\ \\ 16x = 320 \\ x = 320 \div 16 \\ x = 20 \\ \\ 9x + y = 200 \\ 9 \times 20 + y = 200 \\ 180 + y =2 00 \\ y = 200 - 180 \\ y = 20 \\ \\ otvet \: \: (20 \:; \: 20)$

Answer 2

Ответ:

(20; 20)

Пошаговое объяснение:

• ((x + y) / 8) + ((x - y) / 6) = 5
• ((x + y) / 4) + ((x - y) / 5) = 10

• (3(x + y) + 4(x - y)) / 24 = 5
• (5(x + y) + 4(x - y)) / 20 = 10

• (3x + 3y + 4x - 4y) / 24 = 5
• (5x + 5y + 4x - 4y) / 20 = 10

• (7x - y) / 24 = 5
• (9x + y) / 20 = 10

• 7x - y = 120
• 9x + y = 200

• y = 200 - 9x
• 7x - 200 + 9x = 120

• y = 200 - 9x
• 16x = 320

• y = 200 - 9x
• x = 20

y = 200 - 9x = 200 - 180 = 20

Ответ: (20; 20)