Question

giải phương trình: 12-2(x-1)2 = 4(x-2)-(x-3)(2x-5)

Answer 1

<=> 12 - 2(x^2-2x+1) = 4x-8 - 2x^2 +11x-15

<=> 10 - 2x^2 + 4x = -2x^2 + 15x -23 

<=> -11x + 33 =0 <=> x = 3 

Answer 2

\(\Leftrightarrow12-2\left(x^2-2x+1\right)-4x+8+\left(x-3\right)\left(2x-5\right)=0\)

\(\Leftrightarrow-4x+20-2x^2+4x-2+2x^2-5x-6x+15=0\)

=>-11x+33=0

hay x=3

Answer 3

\(\Leftrightarrow\)12-2(x²-2x+1)=2x-8-(2x²-5x-6x+15)
\(\Leftrightarrow\)12-2x²+2x-1=2x-8-2x²+5x+6x-15
\(\Leftrightarrow\)-2x²+2x²+2x-2x-5x-6x=-12+1-8-15
\(\Leftrightarrow\)-11x=-34
\(\Leftrightarrow\)x=\(\dfrac{34}{11}\)
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