a) 9a = ... = 12a

b) ... - 5m = - 2m

c) ... - 3b = 0

N2.

2x - x + 4x - 3x

N3

a) - (x - 5y)

b) x + (2y - 7) - z

N4

c) 4a ・ 16

d) 20c : 5

N5

a) 3 (4k - 5)

b) (b - 3) (-2)

c) 2 (4a + 5) - 4a

N6

(a + b) - (a - b) = (c + b) - (c - b)

N7

4a 3 2a = 6a + 3

4a 3 2a = 2a + 3

4a 3 2a = 24a

4a 3 2a = - 2a

a) 9a + 3a = 12a

b) 3m - 5m = - 2m

c) 3b - 3b = 0

N2.

2x - x + 4x - 3x = 1x + 1x = 2x

N3

a) - (x - 5y) = - x + 5y

b) x + (2y - 7) - z = x + 2y - 7 - z

N4

c) 4a ・ 16 = 64a

d) 20c : 5 = 4c

N5

a) 3 (4k - 5) = 12k - 15

b) (b - 3) (-2) = - 2b + 6

c) 2 (4a + 5) - 4a = 8a + 10 - 4a = 4a + 10

N6

(a + b) - (a - b) = (c + b) - (c - b)

a + b - a + b = c + b - c + b

2b = 2b

N7

4a + 3 + 2a = 6a + 3

4a + 3 - 2a = 2a + 3

4a ・ 3 ・2a = 24a

4a - (3 ・ 2a) = - 2a