5.8×3.6+1.8×8.4
=5.8×2×1.8+1.8×8.4
=11.6×1.8+1.8×8.4
=1.8×(11.6+8.4)
=1.8×20
=36
望采纳
=5.8x3.6+1.8x2x4.2 =5.8x3.6+3.6x4.2 =3.6x(5.8+4.2) =3.6x10 =36
直接计算最简便。
5.8×3.6+1.8×8.4
=20.88+15.12
=36
=5.8x3.6+1.8x2x4.2
=5.8x3.6+3.6x4.2
=(5.8+4.2)x3.6
=10x3.6
=36