[tex]5x^{2}-7x+2=0 \\ \\ 9x^{2}-9x+ \frac{9}{4} - 4x^{2}+2x- \frac{1}{4} \\ \\ (3x- \frac{3}{2} )^{2}-(2x-\frac{1}{2} )^{2} \\ \\ (3x- \frac{3}{2} +2x- \frac{1}{2} )(3x- \frac{3}{2}-2x+ \frac{1}{2} ) \\ \\ (5x-2)(x-1)=0 \\ \\ 5x-2=0 \ \vee \ x-1=0 \\ \\ 5x=2 \ \vee \ x=1 \\ \\ x= \frac{2}{5} \ \vee \ x=1 \\ \\ \boxed{\boxed{x\in \lbrace \frac{2}{5},1 \rbrace }}[/tex]
