[50+(55-x)].17=1700
[50+(55-x)]=1700:17
[50+(55-x)]=100
(55-x)=100-50
(55-x)=50
x=50+55
x=105
720:[31-(2.x-5)]=72
[31-(2.x-5)]=720:72
[31-(2.x-5)]=10
(2.x-5)=31-10
(2.x-5)=21
2.x=21+5
2.x=26
x=26:2
x=13
\(\left[50+\left(55-x\right)\right].17=1700\)
\(50+55-x=1700:17\)
\(105-x=100\)
\(x=105-100\)
\(x=5\)
vay \(x=5\)
2) \(720:\left[31-\left(2x-5\right)\right]=72\)
\(31-2x+5=720:72\)
\(36-2x=10\)
\(2x=36-10\)
\(2x=26\)
\(x=13\)
vay \(x=13\)
[50+(55-x)] .17 =1700
50+(55 - x) =1700 :17
50+(55 - x) =100
55 - x =100 - 50
55-x = 50
x = 55- 50
x =5
1, [ 50+ (55 - x) ] .17= 1700
50+ (55 - x) = 1700 : 17
50+ (55 - x) = 100
55 - x = 100 - 50
55 - x = 50
x = 55 - 50
x = 5
2, 720:[ 31- (2.x-5) ]= 72
31- (2.x-5) = 720 : 72
31- (2.x-5) = 10
2.x-5 = 31 - 10
2.x-5 = 21
2.x = 21 + 5
2.x = 26
x = 26 : 2
x = 13
2)
720:[31-(2x-5)] =72
31-(2x-5) = 720:72
31-(2x-5) = 10
2x-5 =31-10
2x-5 =21
2x =26
x =26 : 2
x = 13
