Question

tìm x biết

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

 

Answer 1

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

=> \(\left(2x+3\right)\left(x-4\right)-\left(3x+5\right)\left(x-4\right)-\left(x-5\right)\left(x-2\right)=0\)

=> \(\left(x-4\right)\left(-x-2\right)-\left(x-5\right)\left(x-2\right)=0\)

=> \(-x^2-2x+4x+8-x^2+2x+5x-10=0\)

=> \(-2x^2+9x-2=0\)

=> \(-\left(x^2-2x+1\right)-\left(x^2-2x+1\right)+5x=0\)

=> \(-\left(x-1\right)^2-\left(x-1\right)^2+5x=0\)

=> \(-2\left(x-1\right)^2+5x=0\)

=> \(2\left(x-1\right)^2-5x=0\)

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để mik giải rồi ghi lại sau nha