[4 5/7x]/2 1/13=2 17/63x
[2 8/9]/3 3/11=143/162
x=[143/162]/[2 17/63]=7/18
<span> 3216:(5y-109)=16</span>
<span><span>(5y-109)=3216:16</span></span>
<span><span><span>5y-109=201</span></span></span>
<span><span><span>5у=201+109</span></span></span>
<span><span><span>5*у=310</span></span></span>
<span><span><span>у=310:5</span></span></span>
<span><span><span>у=62</span></span></span>
<span><span><span>
</span></span></span>
1) 15*(a+2)= 6*(2a+7)
15a+30=12a+42
15a-12a=42-30
3a= 12
a=4
2) 12b-7*(b+4)= 26- 4b
12b-7b-28= 26-4b
5b+4b=26+28
9b= 54
b= 6
3) 5 * (3c + 2) = 8 * (9 - 2c)<span>
15c+10= 72-16c
15c+16c= 72-10
31c=62
c=2
4)</span><span>10k + 2 * (7k - 2 ) = 5 * ( 4k + 3 ) + 3k
10k+ 14k-4=20k+15+3k
24k-4=23k+15
24k-23k=15+4
1k=19
k= 19:1
k=19 </span>
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