MATHmatics(r7 Blame)보기RAWBlame되돌리기비교r7r1Cyber1[[분류:수학]]2<math>20×x×y=20xy</math>3<math>20ax</math>4<math>7bx=2an</math>r4Cyber5[math(|lx|=\dfrac{1}3)]r7Cyber6[math(k)]r4Cyber7[clearfix]r6Cyber8<math>20.</math> [math(\dfrac{b-2}3-\dfrac{1-b}2)]를 간단히 하면? [<math>4</math>점]