a. x - (17 - 8) = 5 + (10 - 3x)
=> x - 9 = 5 + 10 - 3x
=> x + 3x = 15 + 9
=> 4x = 24
=> x = 6
b. 25 - (30 + x) = x - (27 - 8)
=> 25 - 30 - x = x - 19
=> -x -x = -19 + 30 - 25
=> -2x = -14
=> x = 7
c. (x - 12) - 15 = (20 - 7) - (18 + x)
=> x - 12 - 15 = 13 - 18 - x
=> x + x = 13 - 18 + 12 + 15
=> 2x = 22
=> x = 11
Tìm x:
a) x - (17 - 8) = 5 + (10 - 3x)
b) 25 - (30 +x) = x - (27 - 8)
c) (x-12) - 15 = (20 - 7) - (18 + x)
d) 9 - 25 = (7 - x) - (25 + 7)
x - ( 17 - 8 ) = 5 + ( 10 + 3x )
25 - ( 30 + x ) = x - ( 27 - 8 )
( x - 12 ) - 15 = ( 20 - 7 ) - ( 18 + x )
- 5 + 2 / x + 3 / = - 6 - (- 13 )
Dấu / : giá trị tuyệt đối nha
x - ( 17 - 8 ) = 5 + ( 10 + 3x )
25 - ( 30 + x ) = x - ( 27 - 8 )
( x - 12 ) - 15 = ( 20 - 7 ) - ( 18 + x )
-5 + 2 . / x + 3 / = - 6 - ( - 13 )
/ là giá trị tuyệt đối ai làm nhanh nhất k
a,25+[x+17]=0 ; b'20-[x+12]=0 ; c, 15+[5-x]=-7 ; d, 3-5+[-x+3]=6 ; e, 25-[30+x]=x-[27-8] ; f, [x-12]-15=[20-7]-[18+x]
Bài 12: Tính :
a) A = 1 + (-3) + 5 + ( - 7) +….+ 17 + ( -19);
b) B = (- 2) + 4 + (-6) + 8 + …+ ( - 18) + 20;
c) C = 1 + (-2) + 3 + (-4) + ….+ 1999 + ( - 2000) + 2001;
Bài 13: Tìm số nguyên x, biết:
a) –x + 20 = -(-15) –(+8) + 13
b) –(-10) + x = -13 + (-9) + (-6)
tìm x biết,
a)x-13=-5+8
b)|x-2|=|-5|
c)25-(30+x)=x-(27-8)
d)(x-12)-15=(20-7)-(18+x)
a) 16 - 18/x| = -8 -14|x|
b) 5 x|+7.(2/x|-3) =4.(x-4)+25
e) 15-3|4x +2| = 3 8) 18 -4.(6-2|x|) = - 3.(4|x|+5)+29
8) 27-5/x -10 = 4|x-10| - 18
h) 510 + 3x|-21 = 7- 2|15+3x|
c) 43x +2|-16= 20
d) 8|x - 1|-4 = 12+6|x-1|
giúp em với
tìm x
a ) 25 - ( 30 + x ) = x - ( 27 - 8 )
b ) ( x -12 ) -15 = ( 20 - 7 ) - ( 18 + x )
a, 2.x + 7 = 15
b, 25 – 3.(6 – x) = 22
c, [(2x – 11) : 3 + 1].5 = 20
d, (25 – 2x)3 : 5 – 32 = 42
e, 2 . 3x = 10 . 312 + 8 . 274
g, x – 12 = (–8) + (–17)
h, 7 – 2x = 18 – 3x
i, 3(x + 5) – x – 11 = 24
