If the statement is true, state which law the statement illustrates, and then simplify if possible. If the statement is false, write false.

1) (5+3)+7 = 5+(3+7)

2) (5+3)+7 = 7+(5+3)

3) 10-(7-3) = (10-7)-3

4) 36· (12· 3) = (36· 12)· 3

5) (xy)z = (yx)z

6) (xy)z = x(yz)

7) (x-y)(z+3)(a) = (z+3)(x-y)(a)

8) abef = bafe

9) (a+b)(e+f) = (a+b)(f+e)

10) 3(xy) = (3x)(3y)

Simplify using communative & associative laws.

11) (2+5)+(y+7)

12) (p+9)+(n+14)

13) (3+s)+(r+12)

14) (7s)(5t)

15) (4s)(5t)(r· 8)

16) (2+n)+(p+4)+(q+2)

17) (x+y)+(2+p)+(q+4)

18) 4· (3t)

19) 4· (a· 7)

20) 23· m· n· 2