Binomial Theorem

Let (x + 10)⁵⁰ + (x $-$ 10)⁵⁰ = a₀ + a₁x + a₂x² + . . . . + a₅₀x⁵⁰, for all x $\in$ R; then ${{{a_2}} \over {{a_0}}}$ is equal to