1.

а) 0.4a*(-5b) = -2ab

б) (2x -1) (-0.2) = -0.4x+0.2

в) 3(-x-1) = -3x - 3

а) -0,2x*(-5y) = xy

б) (-2x-4)*0.1 = -0.2x-0.4

в) -5(2-x) = -10+x

2.

а) (4a-b) - 5a + 3b = 4a-b-5a+3b=(4a-5a)+(3b-b)=-a+2b

б) -(3x - 0.4) + (0.4x - 3) = -3x + 0.4 + 0.4x - 3 = - 2.6x - 2.6

в) 9 - 2(x+1) + x = 9 - 2x - 2 + x = 7 - x

а) -6a - 2a + (8a + b) = -6a - 2a + 8a + b = b

б) (8x - 0.5) - (0.5x - 8) = 8x - 0.5 - 0.5x + 8 = 7.5x +7.5

в) 4 - 3(x - 2) - x = 4 - 3x + 6 - x = 10 - 4x

3.

а) 3(a - 3b) - 5(a - 2b) = 3a - 9b - 5a + 10b = - 2a + b = 3 - 1 = 2

б) -4(a - b) + 2(3a - b) = -4a + 4b + 6a - 2b = 2a + 2b = -3 - 2 = -5

4.

0.4y - 0.6(y-4) +(-1+0.1y) = 0.4y - 0.6y + 2.4 -1 +0.1y = -0.1y + 1.4

2.3y - 1.7(y-2) + 0.3(4-2y) = 2.3y - 1.7y + 3.4 + 1.2 - 0.6y = 4.6

5.

5a - (4a - ( 3a -2)) = 5a-(4a - 3a + 2) = 5a - 4a + 3a - 2 = 4a - 2

6a - ( 5a - (4a - 3)) = 6a - (5a - 4a +3) = 6a - 5a + 4a - 3 = 5a - 3