[tex]a)\\\\c=\frac{2y}{a}+k \ \ |*a \ \ \ \ \ a\neq 0\\\\ca=2y+ka\\\\2y=ca-ka\\\\2y=a(c-k)\ \ |:2\\\\y=\frac{a(c-k)}{2}\\\\\\ca=2y+ka\\\\ca-ka=2y\\\\a(c-k)=2y\ \ |:(c-k)\ \ \neq 0\\\\a=\frac{2y}{c-k}[/tex]
[tex]b)\\\\ cV=b^2y \ \ |:V\\\\c=\frac{b^2y}{V}[/tex]
[tex]cV=b^2y \ \ |:y\\\\b^2=\frac{cV}{y}\\\\ b=\sqrt{\frac{cV}{y}}=\frac{\sqrt{cV}}{\sqrt{y}}\ \ lub \ \ b=-\sqrt{\frac{cV}{y}}=-\frac{\sqrt{cV}}{\sqrt{y}}[/tex]
