38+5.(x-9)=123
(125 -679 + 145 ) - ( 125 - 679 )
(x - 29 ) - ( 17 - 38 ) = -9
( x + 5 ) + ( x - 9 ) = x + 2
( 27 - x )+ ( 15 + x ) = x - 24
-359 + 181 + ( -123 ) + 350 + ( -172 )
13 - 12 + 11 + 10 - 9 + 8 - 7 -6 + 5 - 4 + 3 + 2 -1
a) (125 -679 + 145 ) - ( 125 - 679 )=125 -679+145-125+679=145
b)(x - 29 ) - ( 17 - 38 ) = -9
<=> x-29 -17+38=-9
<=>x=-1
c)( x + 5 ) + ( x - 9 ) = x + 2
<=>x+5+x-9=x+2
<=>x+x-x=2+9-5
<=>x=6
d) ( 27 - x )+ ( 15 + x ) = x - 24
<=> 27-x+15+x-x=-24
<=> -x=-66
<=>x=66
e) -359 + 181 + ( -123 ) + 350 + ( -172 ) = (181 +350)-(359+172) -123 =531-531-123=-123
f) 13 - 12 + 11 + 10 - 9 + 8 - 7 -6 + 5 - 4 + 3 + 2 -1=( 13 - 12) +11 + (10 - 9)+(8-7)-6+(5-4)+3+(2-1)=1+11+1+1-6+1+3+1=13
a, (125 -679 + 145 ) - ( 125 - 679 )
= 125 - 679 + 145 - 125 + 679
= ( 125 - 125 ) + ( -679 + 679 ) + 145
= 0 + 0 +145
= 145
b, (x - 29 ) - ( 17 - 38 ) = -9
x - 29 - 17 + 38 = -9
x - 29 - 17 = -9 - 38
x - 29 - 17 = -47
x - 29 = -47 + 17
x - 29 = -30
x = -30 + 29
x = -1
Vậy x = -1
c, ( x + 5 ) + ( x - 9 ) = x + 2
x + 5 + x - 9 = x + 2
x - x + 14 = x + 2
14 = x + 2
x = 14 - 2
x = 12
Vậy x = 12
d, ( 27 - x )+ ( 15 + x ) = x - 24
27 - x + 15 + x = x - 24
42 + ( -x + x ) = x - 24
42 = x - 24
x = 24 + 42
x = 66
Vậy x = 66
e, -359 + 181 + ( -123 ) + 350 + ( -172 )
= ( -359 + 350 ) + [ 181 + ( -172 ) ] + ( -123)
= (-9) + 9 + ( -123 )
= 0 + ( -123)
= (-123)
g , 13 - 12 + 11 + 10 - 9 + 8 - 7 -6 + 5 - 4 + 3 + 2 -1
= ( 13 - 12 ) + ( 10 - 9 ) + ( 8 - 7 ) + ( 5 - 4 ) + ( 2 - 1 ) + ( 11 - 6 + 3)
= 1 + 1 + 1 + 1 + 1 + 8
= 1. 5 + 8
= 5 + 8
= 13
123-5(x+4)=38
\(123-5\left(x+4\right)=38\\ 5\left(x+4\right)=85\\ x+4=17\\ x=13\)
\(123-5\left(x+4\right)=38\)
\(\Rightarrow123-5x-20=38\)
\(\Rightarrow-5x=-65\)
\(\Rightarrow x=13\)
Vậy: ...
\(123-5x-20=38\Leftrightarrow123-5x=58\Leftrightarrow5x=65\Leftrightarrow x=13\)
Tìm x A, 123-5(x+4)=38
`123-5(x+4)=38`
`5x-20=123-38`
`5x-20=85`
`5x=85+20`
`5x=105`
`x=105:5`
`x=21`
123-5.(x+4)=38
5x-20=123-38
5x-20=85
5x=85+20
5x=105
x=105:5
x=21
c) (7x + x – 28) :100 – 38 = 9.
d) 936 – (4x + 5x ) = 900
e) 280 + 78 : (135 – x :7) =286
f) x – 18 :3 = 16 + 16 : 23.
g) (3x – 10) : 10 = 20.
h) (3x – 24 ).73= 2.74
i) 123 – 5.( x + 4) = 38.
k) [(6x – 72) :2 – 84].28 = 5628.
m) 2x – 138 = 23.32.
n) [(10 - x).2 + 7]:3 -2 = 3.
Trình bày kết quả rõ ràng nha cảm ơn mọi người rất nhiều❤❤❤
c) (7x + x – 28) :100 – 38 = 9
<=> 8x - 28 = 4700
<=> x = 591
d) 936 – (4x + 5x ) = 900
<=> 9x = 36
<=> x = 4
123 – 5 .( x : 2 + 4 ) = 38
\(123-5\left(x:2+4\right)=38\\ \Rightarrow5\left(x:2+4\right)=85\\ \Rightarrow x:2+4=17\\ \Rightarrow x:2=13\\ \Rightarrow x=26.\)
\(123-5\left(x:2+4\right)=38\)
\(5\left(x:2+4\right)=123-38\)
\(5\left(x:2+4\right)=85\)
\(x:2+4=85:5\)
\(x:2+4=17\)
\(x:2=17-4\)
\(x:2=13\)
\(x=13.2\)
\(x=26\)
\(123-5\left(x:2+4\right)=38\\ 5\left(x:2+4\right)=85\\ x:2+4=17\\ x:2=13\\ x=26\)
123-5 . [x+4]=38
123 - 5 . ( x + 4 ) = 38
5 . ( x + 4 ) = 123 - 38
5 . ( x + 4 ) = 85
x + 4 = 85 : 5
x + 4 = 17
x = 17 - 4
=> x = 13
123-5.(x+4)=38
=>5.(x-4)=123-38
=>5.(x-4)=85
=>x-4=85:5
=>x-4=17
=>x=17+4
=>x=21
123-5 . (x+4) =38
5.(x+4)=123-38
5.(x+4)=85
x+4=85:5
x+4=17
x=17-4
x=13
123-5(x+4)=38
Giải:
\(123-5\left(x-4\right)=38\)
\(\Leftrightarrow5\left(x-4\right)=123-38\)
\(\Leftrightarrow5\left(x-4\right)=85\)
\(\Leftrightarrow x-4=\dfrac{85}{5}\)
\(\Leftrightarrow x-4=17\)
\(\Leftrightarrow x=17+4\)
\(\Leftrightarrow x=21\)
Vậy \(x=21\).
Chúc bạn học tốt!!!
123-5(x+4)=38
5(x+4)=38
5(x+4)=123-38
5(x+4)=85
x+4=85:5
x+4=17
x=17-4
x=13
Chúc bạn học tốt nha
123 - 5 . ( x + 4 ) = 38
123 - 5 . ( x + 4 ) = 38
5 . ( x + 4 ) = 123-38
5 . ( x + 4 ) = 85
5 . ( x + 4 ) = 85
( x + 4 ) = 85 : 5
( x + 4 ) = 17
x = 17 - 4
x = 13
Vậy x=13
123 - 5 . ( x + 4 ) = 38
5 . ( x + 4 ) = 123-38
5 . ( x + 4 ) = 85
5 . ( x + 4 ) = 85
( x + 4 ) = 85 : 5
( x + 4 ) = 17
x = 17 - 4
x = 13
123 - 5 . ( x + 4 ) = 38
5 . ( x + 4 ) = 123 - 38
5 . ( x + 4 ) = 85
x + 4 = 85 : 5
x + 4 = 17
x = 17 - 4
x = 13
123-5.(x +4)=38
\(123-5.\left(x+4\right)=38\)
\(5.\left(x+4\right)=123-38\)
\(5.\left(x+4\right)=85\)
\(x+4=85\div5\)
\(x+4=17\)
\(x=17-4\)
\(x=13\)
Chúc bn hk tốt nhoa :)
123-5.(x+4)=38
5.(x+4)=123-38
5.(x+4)=85
x+4 =85:5
x+4=17
x =17-4
x = 13
123-5.(x+4)=38
5.(x+4)=123-38
5.(x+4)=85
x+4=85:5
x+4 =17
x =17-4
x =13
Chúc bn học tốt