\(x+x+x+x+x+x+x+x+999=456+572\)
\(\Rightarrow1x+1x+1x+1x+1x+1x+1x+1x+999=1028\)
\(\Rightarrow\left(1+1+1+1+1+1+1+1\right)x=1028-999\)
\(\Rightarrow8x=27\Rightarrow x=27\div8=\frac{27}{8}\)
x + x + x + x + x +x + x + x + 999 = 456 + 572
<=>(1 + 1 + 1 + 1 + 1+ 1 + 1 + 1).x + 999 = 1028
<=>8x + 999 = 1028
<=>8x = 1028 - 999
<=>8x = 29
<=>x=3.625
Thử lại
3,625 + 3,625 + 3,625 + 3,625 + 3,625 + 3,625 + 3,625 + 3,625 + 999 = 456 + 572
1028 = 1028
Trl:
\(x+x+x+x+x+x+x+x+999=456+572\)
\(\Rightarrow8x+999=1028\)
\(\Rightarrow8x=1028-999\)
\(\Rightarrow8x=29\)
\(\Rightarrow x=3,625\)
Hc tốt
x + x + x + x + x + x + x + x + 999 = 456 + 572
=> 8x+999= 1028
8x= 1028-999
8x=29
x= 29: 8
x= 3, 625