a) (2x-32):16=3
2x-32=3.16
2x-32=48
2x=48+32
2x=80
x=80:2
x=40
b) (7x -8:2):5=8
(7x-4):5=8
7x-4=8.5
7x-4=40
7x=40+4
a) (2x - 32) : 16 = 3 \(=\left(2x-32\right)=3.16=48\)
= \(\left(2x-32\right)=48\)
= \(2x=48+32=80\)
= \(2x=80\Rightarrow x=80:2=40\)
b) ( 7x - 8 :2) : 5 = 8
= \(\left(7x-8:2\right)=8.5=40\)
= \(\left(7x-8:2\right)=40\)
= \(\left(7x-8\right)=40.2=80\)
= \(\left(7x-8\right)=80\)
= \(7x=80+8=88\)
=>x = 88 : 7 = ......
c) 215 + ( x - 21) : 2 = 235
\(=\left(x-21\right):2=235-215=20\)
= \(\left(x-21\right):2=20\)
= \(\left(x-21\right)=20.2=40\)
= \(\left(x-21\right)=40\)
= \(\Rightarrow x=40+21=61\)
a, ( 2x - 32 ) : 16 = 3
( 2x - 32 ) = 3 x 16
2x - 32 = 48
2x = 48 + 32
2x = 80
x = 80 : 2
x = 40
b, ( 7x - 8 : 2 ) : 5 = 8
( 7x - 8 : 2 ) = 8 x 5
( 7x - 8 : 2 ) = 40
7x x 4 = 40
7x = 40 : 4
7x = 10
x = 10 : 7
c , 215 + ( x - 21 ) : 2 = 235
215 + ( x - 21 ) = 235 x 2
215 + ( x - 21 ) = 470
( x - 21 ) = 470 - 215
x - 21 = 255
x = 255 + 21
x = 276
a) x = 40
b) đề sai
c) x = 61
bn xem lại câu b đi, đề sai rồi
