78.9-(38.89-x(乘)0.4)=50 乘号不会打用(乘)代替 用方程解,
问题描述:
78.9-(38.89-x(乘)0.4)=50 乘号不会打用(乘)代替 用方程解,
答
78.9-(38.89-x*0.4)=50
78.9-(38.89-0.4x)=50
78.9-38.89+0.4x=50
0.4x=50-40.01
0.4x=9.99
x=24.975