Безотлагательно Н 102 и 103, даю 34 балла

102.

1)

(23 + 620 - 745)*5 - 60 = (215 + 6100 - 7225) - 60 =

= 215 + 6*10 - 7*15 - 60 = 60 + 60 - 105 - 60 = -45,

2)

(7 - 23)(23 + 7) - (6 - 32) =

= 7 - 4*3  -  6 + 618 - 9*2 = 7 - 12 - 6 + 182 - 18 = 182 - 29,

3)

(5 - 2) + (3 + 2) = 25 - 102 + 2  +  9 + 62 + 2 = 38 - 42,

4)

((9 - 45) - (9 + 45) = (9 - 45) - 2*(9 - 45)(9 + 45) + (9 + 45) =

= 9 - 45  -  162 + 160  +  9 + 45 = 16,

103.

1)

(х-13)/(х-13) = (х-13)(х+13)/(х-13) = х + 13,

2)

(х+11)/(х-121) = (х+11)/(х-11)(х+11) = 1/(х - 11),

3)

(в-5в)/(в-25) = в*(в-5)/(в-5)(в+5) = в/(в + 5),

4)

(15+15)/15 = 15*(15+1)/15 = 15 + 1,

5)

(х+16х+64)/(х-64) = (х+8)/(х-8)(х+8) = (х + 8)/(х - 8),

6)

(5-10)/(10-2) = (5 - (5*2)) / ((5*2) - 2) =

= 5*(5 - 2) / (2 * (5 - 2)) = 5 / 2 = (5/2) = 2,5