Kouchnirenko's Conjecture:
Let $f_1=f_2=\ldots=f_k=0$ be a system of polynomial equations in $k$ variables and let $m_i$ be the number of terms in $f_i$ . The number of non-degenerate positive roots of this system is less or equal to $(m_1-1)(m_2-1)\ldots(m_k-1)$ .