55~61p:ㄱㄷㅅ/5/3/7000-10분의7ab원/ㄷㄹㅁㅅ/2(ab+bc+ca)cm제곱/20x+2y+1/-89/-3/3/-3분의26/-6분의31/-1/ㄱㄷㄹ/동류항:3x,3분의x,-2분의5x,계수의합6분의5
당신은 어느 그룹입니까?