已知2x=8,那么4x+2×0.8=( ) A.14.4 B.0.4 C.17.6 D.18
问题描述:
已知2x=8,那么4x+2×0.8=( )
A. 14.4
B. 0.4
C. 17.6
D. 18
答
由2x=8得x=4,
将x=4代入4x+2×0.8,
得4×4+2×0.8,
=16+1.6,
=17.6;
故选:C.