Question

tính hợp lý
87 x (- 17) + (- 83) x 87
(- 45) x (1 + 432) - 432 x (- 45)

Answer 1

=87.(-17+(-83)=87.(-100)=-8700

=-45.(1+432-432)=-45.1=-45

Answer 2

a, =87[-17+(-83)]

=87.(-100)

=-8700

b, =(-45)+-(45).432-432.(-45)

(-45)+(-45)(432-432)

=(-45)+0

=-45

Answer 3

tính hợp lý
87 x (- 17) + (- 83) x 87

= 87.[-17+(-83)]

=87.(-100)

=-8700
(- 45) x (1 + 432) - 432 x (- 45)

=-45.433-432.(-45)

=-45.(433-432)

=-45.1

=-45

Answer 4

= 87 x ( - 83 + - 17 )

= 87 x ( - 100 )

= - 8700

= - 45 x ( 432 - 432 ) + 1

= - 45 x 0 + 1

= 1

Answer 5

Trả lời: 

\(a,\)\(87.\left(-17\right)+\left(-83\right).87\)

\(=87.\left(-17-83\right)\)

\(=87.\left(-100\right)\)

\(=-8700\)

\(b,\)\(\left(-45\right).\left(1+432\right)-432.\left(-45\right)\)

\(=\left(-45\right).\left(1+432-432\right)\)

\(=\left(-45\right).1\)

\(=-45\)

Hok tốt! 

Vuong Dong Yet