ПОМОГИТЕ РЕШИТЬ,СРОЧНО, ПОЖАЛУЙСТА,50 БАЛЛОВ,желая бы 1-2

1a) (m + 7) - (m - 7) = m + 14m + 49 - (m - 14m + 49) =

= m + 14m + 49 - m + 14m - 49 = 28m

1б) 8a - (a +5) = 8a - (a + 10a + 25) = 8a - a - 10a - 25 = 7a - 10a - 25

1в) (c + 3) - (c - 4)(c + 4) = c + 6c + 9 - c + 16 = 22c + 9

1г) (x + 6) - x(x - 12) = x + 12x + 36 - x + 12x = 24x + 36

2a) (2x - 5) - (2x - 3)(2x + 3) = 0

4x - 20x + 25 - 4x + 9 = 0

- 20x + 34 = 0

- 20x = - 34

x = 1,7

2б) (x + 1) - (2x - 1) = 0

x + 2x + 1 - 4x + 4x - 1 = 0

- 3x + 6x = 0

x - 2x = 0

x(x - 2) = 0

x = 0                x - 2 = 0

                        x = 2

2в) (x - 6) -x(x + 8) = 2

x - 12x + 36 - x - 8x = 2

- 20x = 2 - 36

- 20x = - 34

x = 1,7

2г) (y - 2) = y(y + 2)

y - 4y + 4 - y - 2y = 0

- 6y + 4 = 0

- 6y = - 4

y = 2/3

3a) 49a - 25b = (7a) - (5b) = (7a - 5b)(7a + 5b)

3б) 27x - 8 = (3x) - 2 = (3x - 2)(9x + 6x + 4)

3в) 125x + 64y = (5x) + (4y) = (5x + 4y)(25x - 20xy + 16y)

3г) (3x - 7) = (3x - 7)(3x - 7)