Question

tính bằng cách hợp lí

1/ -135-2017+9.15

2/ -39.( 250-87) - 61.( 240+97)

3/ 65+135-35+9.35

4/ -15. (23+157)+15.157-15.7

ai giải nhanh, giải hết mik tích cho ^^

Answer 1

-2017

-26914

480

-450

Answer 2

1) - 135 - 2017 + 9 x 15

= - 135 - 2017 + 135

= ( - 135 + 135 ) - 2017

= 0 - 2017

= - 2017

2) - 39 x ( 250 - 87 ) - 61 x ( 240 + 97 )

= - 39 x 163 - 61 x 337

= - 6357 - 20557

= - 26914

3) 65 + 135 - 35 + 9 x 35

= 65 + 135 - 35 + 315

= ( 65 + 315 ) + ( 135 - 35 )

= 380 + 100

= 480

4) - 15 x ( 23 + 157 ) + 15 x 157 - 15 x 7

= 15 x ( - 180 ) + 15 x 157 - 15 x 7 

= 15 x ( - 180 + 157 - 7 )

= 15 x ( - 30 )

= - 450