(3x – 6).3 = 34
219 – 7(x + 1) = 100 ; b) (3x - 6).3 = 34
a)
219-7(x+1)=100
=>7(x+1)=219-100
=>7(x+1)=119
=>x+1=119:7
=>x+1=17
=>x=16
A) 7(X+1)=219-100
7(x+1)=119
x+1=17
x=17+1
x=18
b)3x.6=54:3
3x.6=18
3x=18:6
3x=3
x=3:3
x=1
xin loi to nham = 16
Tìm x, y biết
a,/2x/+/y-3/=0
b,/3x-6/+/3x-y+5/=0
c,34-2./9-3x/=0
tìm x thuộc Z
-2(-34-7x)+5c(-3x-14)=2
-13(-7+3x)-(-985+91)=20(-34-x)-6(3x-16)
Tìm x thuộc N
b, ( 5x + 34 ) . 6^8 = 3^4 . 6^9
c, 5^3 ( 3x + 2 ) : 13 = 10^3 : ( 13^5 : 13^4 )
Giải các phương trình sau: 3 x - 3 4 + 4 x - 10 , 5 10 = 3 x + 1 5 + 6
3 x - 3 4 + 4 x - 10 , 5 10 = 3 x + 1 5 + 6 ⇔ 3 x - 9 4 + 4 x - 10 , 5 10 = 3 x + 3 5 + 6
⇔ 5(3x – 9) + 2(4x – 10,5) = 4(3x + 3) + 6.20
⇔ 15x – 45 + 8x – 21 = 12x + 12 + 120
⇔ 15x + 8x – 12x = 12 + 120 + 45 + 21
⇔ 11x = 198
⇔ x = 18
Phương trình có nghiệm x = 18
(3x-6)x3=34
(3x-6)x3=34
3x-6=34:3
3x-6=34/3
3x=34/3+6
3x=52/3
x=52/3:3
x=52/9 tick tui nha Dương Ngọc Quỳnh Anh
Bài 6: Tìm số nguyên x,biết:
a) x+ 118 =218 |
b) 18 – x =-17 |
c) (-18) – x =-17 |
d)124 +(118 – x)=217 |
e) (3x – 6).3 = 34 |
g) 23.(42 – x) = 46 |
h) 84 – (3x + 8) = 34 |
i) 3(2x + 1) -19 = 14 |
k) 6x – 302 = 23.5 |
m) (x -1)2 = 81 |
n) 2x+1- 5 =27 |
m) 2x+ 2x+1+ 2x+2 = 56 |
a) x + 118 = 218
x = 218 – 118
x = 100
b) 18 – x = -17
X = 18 – (-17)
X = 35
c) (-18) – x = -17
X = (-18) – (-17)
X = -1
d)124 + (118 – x) = 217
118 – x = 93
X = 118 – 93
X = 25
e) (3x – 6).3 = 34
(3x – 6).3 = 81
3x – 6 = 27
3x = 33
ð X = 11
g) 23.(42 – x) = 46
42 – x = 2
ð X = 40
h) 84 – (3x + 8) = 34
3x + 8 = 84 – 34
3x + 8 = 50
3x = 50 – 8
3x = 42
X = 42 : 3
ð X = 14
i) 3.(2x + 1) – 19 = 14
3.(2x + 1) = 14 + 19
3.(2x + 1) = 33
2x + 1 = 33 : 3
2x + 1 = 11
2x = 11 – 1
2x = 10
X = 10 : 2
ð X = 5
k) 6x – 302 = 23.5
6x – 302 = 40
6x = 40 + 302
6x = 342
X = 342 : 6
ð X = 57
m) (x – 1)2 = 81
(x – 1)2 = 92
ð X – 1 = 9
ð X = 9 + 1
ð X = 10
n) 2x+1 – 5 = 27
2x+1 = 27 + 5
2x+1 = 32
2x+1 = 25
ð X = 4
a) \(x+118=218\)
\(x=218-118\)
\(x=100\)
b)\(18-x=-17\)
\(-x=-18-17\)
\(-x=-35\)
\(x=35\)
c)\(\left(-18\right)-x=-17\)
\(-x=18-17\)
\(-x=1\)
\(x=-1\)
d)\(124+\left(118-x\right)=217\)
\(118-x=217-124\)
\(118-x=93\)
\(x=25\)
e) \(\left(3x-6\right).3=3^4\)
\(3x-6=3^3\)
\(3x-6=27\)
\(x=11\)
g)\(23.\left(42-x\right)=46\)
\(42-x=2\)
\(x=40\)
h) \(84-\left(3x+8\right)=34\)
\(3x+8=50\)
\(x=14\)
i) \(3\left(2x+1\right)-19=14\)
\(3\left(2x+1\right)=33\)
\(2x+1=11\)
\(x=5\)
k) \(6x-302=2^3.5\)
\(6x-302=8.5\)
\(x=57\)
m) \(\left(x-1\right)^2=81\)
\(\left(x-1\right)^2=9^2\)
\(x-1=9\)
\(x=10\)
n) \(2^{x+1}-5=27\)
\(2^{x+1}=32\)
\(2^{x+1}=2^5\)
\(x+1=5\)
\(x=4\)
m) \(2^x+2^{x+1}+2^{x+2}=56\)
\(2^x.1+2^x.2+2^x.2^2=56\)
\(2^x\left(1+2+4\right)=56\)
\(2^x=8\)
\(2^x=2^3\)
\(x=3\)
\(2^x=8\)
Hãy giải các phương trình sau đây :
1, x2 - 4x + 4 = 0
2, 2x - y = 5
3, x + 5y = - 3
4, x2 - 2x - 8 = 0
5, 6x2 - 5x - 6 = 0
6,( x2 - 2x )2 - 6 (x2 - 2x ) + 5 = 0
7, x2 - 20x + 96 = 0
8, 2x - y = 3
9, 3x + 2y = 8
10, 2x2 + 5x - 3 = 0
11, 3x - 6 = 0
1) Ta có: \(x^2-4x+4=0\)
\(\Leftrightarrow\left(x-2\right)^2=0\)
\(\Leftrightarrow x-2=0\)
hay x=2
Vậy: S={2}
120 + ( 34 + 3x ) + ( 6 + x ) = 0
120 + (34 + 3x) + (6 + x) = 0
=> 120 + 34 + 3x + 6 + x = 0
=> (120 + 34 + 6) + (3x + x) = 0
=> 160 + 4x = 0
=> 4x = -160
=> x = -160:4
=> x = -40
120 + (34 + 3x) + (6 + x) = 0
120 + 34 + 3x + 6 + x = 0
(120 + 34 + 6) + (3x + x) = 0
160 + 4x = 0
4x = -160
x = -160:4
=> x = -40