18. Решите уравнения: 1) 7x-2x-3x-37=73; 2) 6y-3y+4y-14=-77; 3) 8x-10x-4x-23=13; 4) 6y-11y+2y+12=-36.

Решение:

1. \( 7x - 2x - 3x - 37 = 73 \)
   \[ (7-2-3)x - 37 = 73 \]
   \[ 2x - 37 = 73 \]
   \[ 2x = 73 + 37 \]
   \[ 2x = 110 \]
   \[ x = \frac{110}{2} \]
   \[ x = 55 \]
2. \( 6y - 3y + 4y - 14 = -77 \)
   \[ (6-3+4)y - 14 = -77 \]
   \[ 7y - 14 = -77 \]
   \[ 7y = -77 + 14 \]
   \[ 7y = -63 \]
   \[ y = \frac{-63}{7} \]
   \[ y = -9 \]
3. \( 8x - 10x - 4x - 23 = 13 \)
   \[ (8-10-4)x - 23 = 13 \]
   \[ -6x - 23 = 13 \]
   \[ -6x = 13 + 23 \]
   \[ -6x = 36 \]
   \[ x = \frac{36}{-6} \]
   \[ x = -6 \]
4. \( 6y - 11y + 2y + 12 = -36 \)
   \[ (6-11+2)y + 12 = -36 \]
   \[ -3y + 12 = -36 \]
   \[ -3y = -36 - 12 \]
   \[ -3y = -48 \]
   \[ y = \frac{-48}{-3} \]
   \[ y = 16 \]

Ответ: 1) x = 55; 2) y = -9; 3) x = -6; 4) y = 16.