\[ y''(x)=0 \] ✓ Mathematica : cpu = 0.0031917 (sec), leaf count = 12
\[\{\{y(x)\to c_2 x+c_1\}\}\] ✓ Maple : cpu = 0.005 (sec), leaf count = 9
\[y \relax (x ) = c_{1} x +c_{2}\]
Hand solution
\[ y^{\prime \prime }=0 \]
Integration twice gives
\[ y\relax (x) =c_{1}x+c_{2}\]