△、○、☆都不等于0，○代表的数是几？6v'c1x4f,V9C;T-W3U)q
△×○=☆6v'c1x4f,V9C;T-W3U)q
△＋△＋△=☆－△－△6v'c1x4f,V9C;T-W3U)q
○=-t'q.h/^:E1i)Y7i0I(c2A4]:G2P6v'c1x4f,V9C;T-W3U)q
算式：提示;q4D.l*i:T._(m3W(J(O6v'c1x4f,V9C;T-W3U)q