(本题5分)已知:如图,AB=AD,AC=AE,∠BAC=∠DAE.求证:BC=DE.
(本题5分)分解因式:.
(本题4分)计算:.
16的平方根为_________.
0.01的平方根是_____,-27的立方根是______,的相反数是_ _.
2-的相反数是 ,绝对值是 .