解方程:1.(1/2-9)X1/5=X-9 2.1/19x+(1540-x)x1/10=100 3.3/5x X18+2/5x X(18-10)=2870
问题描述:
解方程:1.(1/2-9)X1/5=X-9 2.1/19x+(1540-x)x1/10=100 3.3/5x X18+2/5x X(18-10)=2870
答
1.(1/2-9)X1/5=X-9x=9+1/10-9/5x=7又3/102.1/19x+(1540-x)x1/10=10010x+(1540-x)x19=100x19010x+1540x19-19x=100x1909x=(1540-1000)x19x=11403.3/5x X18+2/5x X(18-10)=28703/5x X18+2/5x X18-4x=2870(3/5+2/5)...