Question

Решите систему уравнений способом подстановки.
2х + у = 2,
4х - 3 к = 24.


3х + 2 у= 6,
2х - у= 1.

Answer 1

1)

$left {{{2x + y = 2} atop {4x -3y = 24}} right\left { {{y=2 - 2x} atop {4x -3y = 24}} right. \4 x - 3 * (2 - 2x) = 24\4x - 6 + 6x = 24\4x + 6x = 24 + 6\10x = 30\x = frac{30}{10} = 3\y = 2 - 2 * 3 = 2 - 6 = -4$

2)

$left { {{3x + 2y = 6} atop {2x - y = 1}} right. \left { {{3x + 2y = 6} atop {y = -1 + 2x}} right. \\3x + 2 * (-1 + 2x) = 6\3x - 2 + 4x = 6\7x = 6 + 2\7x = 8\x = frac{8}{7}\y = -1 + 2 * frac{8}{7} = -1 + frac{16}{7} = frac{-7 + 16}{7} = frac{9}{7}$