a) 25 - ( 25 - x ) = 12 + ( 42 - 65 )
a) 25 - ( 25 - x ) = 12 + ( 42 - 65 )
\(25-\left(25-x\right)=12+\left(42-65\right).\)
\(\Leftrightarrow25-25+x=12-23.\)
\(\Leftrightarrow x=-11.\)
Vậy \(x=-11.\)
25 - ( 25 - x ) = 12 + ( 42 - 65 )
25 - ( 25 - x ) = 12 + (-23)
25 - ( 25 - x ) = -11
25 - x = 25 - (-11)
25 - x = 36
x = 25 - 36
x = -11
25−(25−x)=12+(42−65).25−(25−x)=12+(42−65).
⇔25−25+x=12−23.⇔25−25+x=12−23.
⇔x=−11.⇔x=−11.
Vậy x=−11.
g) (15 + 37) + (52 – 37 – 17) h) (38 – 42 +14) - (38 – 42 - 15) i) (27 + 65 ) + (346 - 27- 65) k) - (27 + 65) - (346 – 27 - 65) l) (42 – 69 + 17) - (42 + 17) m) 24. (16 - 5) – 16. (24 – 5 ) n) (-12). 47 – 12 . 52 + (-12) p) 51 . (69 - 25) – 69. (51 - 25) |
g) (15 + 37) + (52 – 37 – 17) = 15 + 37 + 52 – 37 – 17 = 15 + 52 – 17 = 50 h) (38 – 42 +14) - (38 – 42 - 15) = 38 – 42 +14 - 38 + 42 + 15 = 14 + 15 = 29 i) (27 + 65 ) + (346 - 27- 65) = 27 + 65 + 346 - 27- 65 = 346 k) - (27 + 65) - (346 – 27 - 65) = -27 - 65 - 346 + 27 + 65 = -346 l) (42 – 69 + 17) - (42 + 17) = 42 – 69 + 17 - 42 - 17 = – 69 m) 24. (16 - 5) – 16. (24 – 5 ) = 24. 16 - 24 . 5 - 16 . 24 + 16. 5 = - 24 . 5 + 16. 5 = -8 . 5 = -40 n) (-12). 47 – 12 . 52 + (-12) = -12 (47 - 52 + 1) = -12 . (-4) = 48 p) 51 . (69 - 25) – 69. (51 - 25) = 51 . 69 - 51 . 25 – 69. 51 + 69. 25 = - 51 . 25 + 69. 25 = (- 51+ 69).25 = 450 |
4)tìm x:
a) 25 - ( 25 - x ) = 12 + ( 42 - 65 )
b) 215 + (-38) - 54 + 90 - ( -48 + x )=0
c) 15 - ( 15 + x ) = 21
d) 39 + ( x - 39 ) = 50
e) 13 - ( 25 - x)=7
g) x - 15 = -21
i) 12 - (30-x)= -23
k) 31 - ( 17+x) = 18
m) |x| - 5 = 12
a) \(25-\left(25-x\right)=12+\left(42-65\right)\)
\(25-\left(25-x\right)=12+\left(-23\right)\)
\(25-\left(25-x\right)=-11\)
\(25-x=25-\left(-11\right)\)
\(25-x=36\)
\(x=25-36\)
\(x=-11\)
Làm 2 câu dài cho bạn nhá! Mấy câu ngắn tương tự!
a, \(25-\left(25-x\right)=12+\left(42-65\right)\)
\(\Rightarrow25-25+x=12+42-65\)
\(\Rightarrow x=-11\)
b, \(215+\left(-38\right)-54+90-\left(-48+x\right)=0\)
\(\Rightarrow215-38-54+90+48-x=0\)
\(\Rightarrow x=261\)
m, \(\left|x\right|-5=12\)
\(\Rightarrow\left|x\right|=17\Rightarrow\left\{{}\begin{matrix}x=-17\\x=17\end{matrix}\right.\)
Chúc bạn học tốt!!!
a)25-(25-x)=12+(42-65)
b)31-(17+x)=18
c)5+l x+3 l = 9
d)x-(25+x)=13-x
e)15-(30+x)=x-(27-l-8l)
f)[(10-x).2+51]:3-2=3
g)(x-12)-15=20-(17+x)
h)-12-l13-xl=-21
i)8<lx-6l<9
mọi người giúp mk với, mk đang cần gấp
a, 29 + 131 + 237 + 763 b, 65 + 327 + 15 + 73 c, 12+ 54:18 - 8
d.45.58+ 45.42 e) 35 . 34 + 35 . 26+ 40.35 f. 65 . 25 + 65 . 45+ 30.65
g) 750 : {32 – [ 22 + (5. 32 – 42)]} + 100 h) {630 : [16 + 3.(6 + 3. 4)]} – 1
i) 5871: [928 – ( 247- 82). 5] + 21750 k) 375 : {32 – [ 4 + (5. 32 – 42)]} – 14
1, Tìm số nguyên x ,biết :
a) 25 - ( 25-x) = 12+(42-65)
b) 31 - ( 17+x) = 18 ( *giải bằng 2 cách )
c ) x-( -25+x) = 13-x
d) 15-(30+x) = x-( 27-1-81)
CHIỀU MK PHẢI NỘP GẤP CÁC BẠN GIÚP MK VỚI AI NHANH NHẤT MK SẼ TÍCH
a) 25-(25-x)=12+(42-65)
25-25+x=12+(-23)
0+x=(-11)
x=(-11)-0
x=(-11)
b) Cách 1: 31-(17+x)=18
17+x=31-18
17+x=13
x=13-17
x= (-4)
Cách 2: 31-(17+x)=18
31-17-x=18
14-x=18
x=14-18
x= (-4)
c) x-(-25+x)=13-x
x-(-25)-x=13-x
x-x-(-25)=13-x
0-(-25)=13-x
25=13-x
13-25=x
(-12)=x
Vậy x=(-12)
Thực hiện phép tính (hợp lý nếu có thể)
a) − 105 + − 25 + ( − 105 ) + 50
b) 465 + − 38 + − 465 − 12 − − 42
c) 65. − 19 + − 19 .24 + − 19 .11
d) − 3 2 + 2 3 − − 5 2 + 4 3
a) − 105 + − 25 + ( − 105 ) + 50
= 105 + 25 + ( - 105) + 50
= [105 + ( -105)] + ( 25 + 50 )
= 0 + 75 = 75
b) 465 + − 38 + − 465 − 12 − − 42
= 465 + ( - 38) + ( -465) – 12 – 42
= [ 465 + (- 465) ] – ( 12 + 42 )
= 0 – 54 = 0 + ( -54 ) = -54
c) 65. − 19 + − 19 .24 + − 19 .11
= ( - 19) . ( 65 + 24 + 11 )
= ( -19) . 100 = -1900
d) − 3 2 + 2 3 − − 5 2 + 4 3
= 9 + 8 – 25 + 64 = 56
a, [42-98] - [42-12] - 12
b, [-5] x 4x [-2] x3 x [-25]
a,=-56-30-12 b,=-20.-2.3.25
=-86-12 =40.3.25
=-98 = 120.25
=3000
1. = 13
2. = 346
3.= -69
4. = -2600
5. -2150