急!解方程:x⼀0.5-1⼀0.7=1; y⼀5-(y-1)⼀2=1-(y+2)⼀5

2024-12-28 15:38:13
推荐回答(3个)
回答1:

∵x/0.5-1/0.7=1; y/5-(y-1)/2=1-(y+2)/5
∴2x-10/7=1,y/10=-6/10
∴x=17/14,y=-6

回答2:

x/0.5-1/0.7=1
0.7x-0.5=0.35
0.7x=0.85 x=17/14

回答3:

x/0.5-1/0.7=1;
0.7x-0.5=0.35
0.7x=0.85
x=85/70
x=17/14

y/5-(y-1)/2=1-(y+2)/5
2y-5(y-1)=10-2(y+2)
2y-5y+5=10-2y-4
-3y+2y=6-5
-y=1
y=-1