Question

Tính:

a) 85.(35 - 27) - 35.(85 -27)

b) 47. (45 - 15) - 47.(45+15)

Answer 1

a, 85.(35-27)-35.(85-27)

=85.35-85.27-35.85+35.27

=85.27+35.27

=27.(85+35)

=27.120=3240

b, 47.(45-15)-47.(45+15)

=47.30-47.60

=47.(30-60)

=-1410