Bài 1 :
( 1456+ 23) - 1456 = 23
(- 2019 )- ( 234-2019) =-234
( 116 +124)+( 215-116-124)=215
( 435 - 167 -89) - ( 435-89)=-167
Bài 2 :
a, x - 96 = (443 - x) - 15
=>x - 96 = 443 - x - 15
=>x + x = 443 - 15 + 96
=>2x = 524
=>x = 524 : 2
=>x = 262
b,
(x - 12) - 15 = (20 - 7) - (18 + x)
=>x - 12 - 15 = 20 - 7 - 18 - x
=>x + x = 20 - 7 - 18 + 12 + 15
=>2x = 22
=> x = 22 : 2
=> x = 11
c, x+1-16=-3
/x+1/ =-3+16
/ x+1/ =13
x+1=13 =>x=12
x+1=-13 =>x=-14
d,bạn tự làm theo ý trên
câu 3
