1) 7x + 3 =30-2x; 3) 1-2(5+3x) = 15; 5) (7x+3)-(9x + 7) = 5; 2) 3(x-2) = x + 2; 4)-4x = 15-3(3x-5); 6) 5-2(x-1) = 4-x.

Решение:

• 1) 7x + 3 = 30 - 2x \
  9x = 27 \
  x = 3
• 2) 3(x - 2) = x + 2 \
  3x - 6 = x + 2 \
  2x = 8 \
  x = 4
• 3) 1 - 2(5 + 3x) = 15 \
  1 - 10 - 6x = 15 \
  -9 - 6x = 15 \
  -6x = 24 \
  x = -4
• 4) -4x = 15 - 3(3x - 5) \
  -4x = 15 - 9x + 15 \
  -4x = 30 - 9x \
  5x = 30 \
  x = 6
• 5) (7x + 3) - (9x + 7) = 5 \
  7x + 3 - 9x - 7 = 5 \
  -2x - 4 = 5 \
  -2x = 9 \
  x = -4.5
• 6) 5 - 2(x - 1) = 4 - x \
  5 - 2x + 2 = 4 - x \
  7 - 2x = 4 - x \
  3 = x

Ответ: 1) x = 3; 2) x = 4; 3) x = -4; 4) x = 6; 5) x = -4.5; 6) x = 3.