Tìm x
\(2x.\left(x-5\right)-x.\left(3+2x\right)=26\)
\(\left(x-7\right).\left(x-5\right)-12.\left(3x-7\right)=15\)
\(4.\left(18-5x\right)-12.\left(3x-7\right)=15.\left(2x-16\right)-6.\left(x+14\right)\)
\(\left(x-1\right).\left(x^2+x+1\right)=x^3-2x\)