Given: x=−2,y=35,z=−43
LH.S.:(x+y)+z=(−2+35)+(−43)
=(−2×51×5+35)−43
=(−105+35)−43
=−75−43=−7×35×3−4×53×5
=−2115−2015
=−4115
R.H.S:x+(y+z)=−2+(35+−43)
=−2+(3×35×3−4×53×5)
=−2+(915−2015)
=−2−1115
=−2×151×15−1115
=−3015−1115=−4115
Thus, (x+y)+z=x+(y+z)
Hence, law of associativity is verified.