2.
1)-17х+(20-7х)=28
-17х+20-7х=28
-17х-7х=28-20
-24х=8
х= - 8/24= -1/3
2)-8/15х-(11+4/9х)=11
<span>-8/15х-11-4/9х=11
</span>(-24-20)/45х=11+11
-44/45х=22
-х=22:44/45
х=-990/44=-22,5
<span>5000-(27000+36000):900=4930
1)27000+36000=63000
2)63000:900=70
3)5000-70=4930</span>
2/3 От 24=24÷3×2=16
3/4от36=36÷4×3=27
1/3 от 6= 6÷3×1=2
1/3 От 9 = 9÷3×1=3