1) \(\left(3x-5\right)^2+\left(2x+1\right)^2=\left(5x-6\right)\left(2x+3\right)+3x^2\)
\(\Leftrightarrow\) \(9x^2-30x+25+4x^2+4x+1=10x^2+15x-12x-18+3x^2\)
\(\Leftrightarrow\) \(13x^2-26x+26=13x^2+3x-18\)
\(\Leftrightarrow\) \(-29x+44\) \(\Leftrightarrow\) \(-29x=-44\Leftrightarrow\) \(x=\dfrac{44}{29}\) vậy \(x=\dfrac{44}{29}\)
2) \(\left(7x-4\right)\left(5x+3\right)=\left(6x-5\right)^2-x^2+1\)
\(\Leftrightarrow\) \(35x^2+21x-20x-12=36x^2-60x+25-x^2+1\)
\(\Leftrightarrow\) \(35x^2+x-12=35x^2-60x+26\)
\(\Leftrightarrow\) \(61x-38=0\) \(\Leftrightarrow\) \(61x=38\) \(\Leftrightarrow x=\dfrac{38}{61}\) vậy \(x=\dfrac{38}{61}\)
1. \(\left(3x-5\right)^2+\left(2x+1\right)^2=\left(5x-6\right)\left(2x+3\right)+3x^2\)
\(\Leftrightarrow9x^2-30x+25+4x^2+4x+1=10x^2+15x-12x-18+3x^2\)
\(\Leftrightarrow-29x=-44\)
\(\Rightarrow x=\dfrac{44}{29}\)
2. \(\left(7x-4\right)\left(5x+3\right)=\left(6x-5\right)^2-x^2+1\)
\(\Leftrightarrow35x^2+21x-20x-12=36x^2-60x+25-x^2+1\)
\(\Leftrightarrow61x=38\)
\(\Rightarrow x=\dfrac{38}{61}\)
