a. 0,2 * x + 0,4 * x = 12
(0,2 + 0,4) * x = 12
0,6 * x = 12
x = 12 : 0,6
x = 60
\(0,2\times x+0,4\times x=12\)
\(x\times\left(0,2+0,4\right)=12\)
\(x\times0,6=12\)
\(x=12\div0,6\)
\(x=20\)
\(\left(x-4,5\right)+\left(x+3,5\right)+\left(x-1,5\right)=2\)
\(x-4,5+x+3,5+x-1,5=2\)
\(x+x+x+3,5-4,5-1,5=2\)
\(x\times3=2+1,5+4,5-3,5\)
\(x\times3=4,5\)
\(x=4,5\div3\)
\(x=1,5\)
bạn Rin làm phần a rồi v mình làm phần còn lại nhé
\(\left(x-4.5\right)+\left(x+3.5\right)+\left(x-1.5\right)=2\)
\(< =>x-4.5+x+3.5+x-1.5=2\)
\(< =>3x=4.5-3.5+1.5+2\)
\(< =>3x=4.5\)
\(< =>x=1.5\)
\(\left(a\right)0,2\times x+0,4\times x=12\)
\(x\times\left(0,2+0,4\right)=12\)
\(x\times0,6=12\)
\(x=12\div0,6\)
\(x=20\)
\(\left(b\right)\left(x-4,5\right)+\left(x+3,5\right)+\left(x-1,5\right)=2\)
\(x-4,5+x+3,5+x-1,5=2\)
\(\left(x+x+x\right)-4,5+3,5-1,5=2\)
\(3x-2,5=2\)
\(3x=2+2,5\)
\(3x=4,5\)
\(x=4,5\div3\)\(x=1,5\)
\(0,2\cdot x+0,4\cdot x=12\)
\(< =>\left(0,2+0,4\right)\cdot x=12\)
\(< =>0.6\cdot x=12\)
\(< =>x=20\)