计算:(1);(2);(3)(x≥0,y>0);(4).
(本题12分)计算: (1) (2) (3) (4)
计算下列各题: (1)(-2)+(-8) (2)1+(-2)+|-2-3|-5 (3) (4) (5)﹣3﹣[﹣5+(1﹣2×)÷(﹣2)] (6)25×(-18)+(-25)×12+25×(-10 )
计算(每小题4分,共24分) (1) (2) (3) (4) (5) (6)
计算(每题3分,共12分) (1)8+(-)-5-(-0.25) (2) (3) (4)
计算:(每小题4分,共24分) (1)-5-1+3-7 (2)(—3)+(+8)—(—5) (3) (4) (5)3×(-4)+28÷(-7) (6)