Question

câu 1:5.(-17+3)-28.70+140

câu 2:15.(75+25)-25.915-75)

 

Answer 1

5.(-17+3)-28.70+140

= 5.(-14) -  1960 + 140

= -70 - 1960 + 140

= -2030 + 140

= -1890

Answer 2

con cau 2 nua ban

Answer 3

5 × ( -17 + 3 ) - 28 × 70 + 140 

= 5 × ( -14 ) - 28 × 70 + 140 

= -70 - 1960 + 140 

= -2030 + 140 

= -1890 

15 × ( 75 + 25 ) - 25 × 915 - 75 

= 15 × 75 + 25 - 25 × 915 - 75 

= 15 × ( 25 - 25 ) + ( 75 - 75 ) × 915 

=  15 × 0 + 0 × 915 

= 0 + 0 × 915 

= 0