Question

Tìm xϵ Z biết

a,2.(x+3)-2.(x-3)=x

b,10.(x-7)=8(x-4)+x

c,-4+(5-x)-3(x+2)=-5

Answer 1

a,\(2\left(x+3\right)-2\left(x-3\right)=x\)

\(\Leftrightarrow2x+6-2x+6=x\)

\(\Leftrightarrow12=x\)

Vậy...

b,\(10\left(x-7\right)=8\left(x-4\right)+x\)

\(\Leftrightarrow10x-70=8x-32+x\)

\(\Leftrightarrow10x-8x-x=-32+70\)

\(\Leftrightarrow x=38\)

Vậy...

c,\(-4+\left(5-x\right)-3\left(x+2\right)=-5\)

\(\Leftrightarrow-4+5-x-3x-6=-5\)

\(\Leftrightarrow-x-3x=-5+6-5+4\)

\(\Leftrightarrow-4x=0\)

\(\Leftrightarrow x=0\)

Vậy...