\[ -\text {Global$\grave { }$a}^2+\text {Global$\grave { }$y}'(\text {Global$\grave { }$x})^2+\text {Global$\grave { }$y}(\text {Global$\grave { }$x})^2=0 \] ✓ Mathematica : cpu = 0.0479909 (sec), leaf count = 107
\[\left \{\left \{\text {Global$\grave { }$y}(\text {Global$\grave { }$x})\to -\frac {\text {Global$\grave { }$a} \tan \left (\text {Global$\grave { }$x}-c_1\right )}{\sqrt {\tan ^2\left (\text {Global$\grave { }$x}-c_1\right )+1}}\right \},\left \{\text {Global$\grave { }$y}(\text {Global$\grave { }$x})\to \frac {\text {Global$\grave { }$a} \tan \left (\text {Global$\grave { }$x}-c_1\right )}{\sqrt {\tan ^2\left (\text {Global$\grave { }$x}-c_1\right )+1}}\right \},\left \{\text {Global$\grave { }$y}(\text {Global$\grave { }$x})\to -\frac {\text {Global$\grave { }$a} \tan \left (c_1+\text {Global$\grave { }$x}\right )}{\sqrt {\tan ^2\left (c_1+\text {Global$\grave { }$x}\right )+1}}\right \},\left \{\text {Global$\grave { }$y}(\text {Global$\grave { }$x})\to \frac {\text {Global$\grave { }$a} \tan \left (c_1+\text {Global$\grave { }$x}\right )}{\sqrt {\tan ^2\left (c_1+\text {Global$\grave { }$x}\right )+1}}\right \}\right \}\]
✓ Maple : cpu = 0.745 (sec), leaf count = 68
\[ \left \{ y \left ( x \right ) =a,y \left ( x \right ) =\tan \left ( -x+{\it \_C1} \right ) \sqrt {{\frac {{a}^{2}}{ \left ( \tan \left ( -x+{\it \_C1} \right ) \right ) ^{2}+1}}},y \left ( x \right ) =-a,y \left ( x \right ) =-\tan \left ( -x+{\it \_C1} \right ) \sqrt {{\frac {{a}^{2}}{ \left ( \tan \left ( -x+{\it \_C1} \right ) \right ) ^{2}+1}}} \right \} \]