!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

1. 1) 8,4*(-5,7)=-47,88

2) 28/5 * 25/21 = 20/3 = 6 2/3

3) -24,7

4) 2,07

2. 1) -4,2х*(-6у) = 4,2х*6у = 6(0,7ху)

2) 8m+5p-13m-p = 4p-5m

3) k-(17-k)+(-k+30)=k-17+k-k+30=k+13

4) -6(4+a)+8(a-6)=-24-6a+8a-48=2a-74=2(a-37)

3. (-1,42-(-3,22)):(-0,8)+(-6)*(-0,7)=(-1,42+3,22):(-0,8+4,2)=1,8:3,4= 9/17

4. 5(-1,4a+3)-(1-2,5a)-4(0,8a+3)=-7a+15-1+2,5a-3,2a-12=-7,7a+2=-7,7*5/7 + 2=-5,5+2=-3,5

5. 2(4a+3b)-3(2a+6b)=8a+6b-6a-18b=2a-12b=2(a-6b)=-2(6b-a)=-2*(-1,9)=3,8.