[tex]Zadanie\\\\a)\\\\4a-a^{2} -3\\\\a=-\frac{1}{4}\\\\4\cdot(-\frac{1}{4})-(-\frac{1}{4})^{2}-3=-1- \frac{1}{16}-3=-4\frac{1}{16}\\\\b)\\\\2x^{2} +4y-3+6-4y-2x=2x^{2} -2x+3\\\\x=-3;\ \ \ y=-\frac{1}{2}\\\\2\cdot(-3)^{2}-2\cdot(-3)+3=18+6+3=27[/tex]
