[tex](x-3)^2= \frac{21-17x}{2}[/tex], inmultim egalitatea cu 2 ⇒ [tex]2(x^2-6x+9)=21-17x,sau,2x^2-12x+18-21+17x=0,obtinem[/tex],
2x²+5x-12=0, a=1, b=5, c=-12, calculam
Δ=[tex]b^2-4ac=25+96=121,apoi, x_{1}= \frac{-5- \sqrt{121} }{4}= \frac{-5-11}{4}= -4,si, [/tex][tex] x_{2}= \frac{-5+11}{4}= \frac{6}{4}= \frac{3}{2} [/tex]
