\(420:\left(75-\left(x-10\right)\right)=21\)
\(75-\left(x-10\right)=420:21=20\)
\(x-10=75-20=55\)
\(x=55+10=65\)
420:[75-(x-10)]=21
[75-(x-10)]=420:21
75-(x-10)=20
(x-10)=75-20
x-10=55
x =55+10
x =65
k nếu thấy đúng
420 : (75- (x -10 )) = 21
(75-(x-10) ) = 420 : 21
(75-(x-10)) = 20
( x-10) = 75-20
(x-10) = 55
x = 55+10
x = 65
mik nhanh nhớ kết mik nha!!!!!!!\(I\)\(love\)\(you\)\(!!!!\)