Ta có:\(x.\frac{1}{5}+x.\frac{4}{5}=2\)
=>\(x.\frac{1}{5}+\frac{4}{5}=2\)
=>\(x.\frac{5}{5}=2\)
=>\(x.1=2\)
=>\(x=2:1\)
=>\(x=2\)
1. X x 1/5 + X x 4/5 = 2
X x (1/5 + 4/5) = 2
X x 1 = 2
X = 2 : 1
X = 2
2. 18/21 - 19/32 + 3/21 + 13/32
= (18/21 + 3/21) - (19/32 + 13/32)
= 21/21 - 32/32
= 1 - 1
= 0