tìm x
123 - 5. ( x+4 ) = 38
( 3x - 2^4 ) . 7^3 = 2 . 7^4
Tìm x
a, 123 - 5 . ( x + 4 ) = 38
b, ( 3x - 24 ) . 73 = 2 . 74
c, ( x : 3 - 4 ) . 5 = 15
a) 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
b) (3x - 24) . 73 = 2 . 74
3x - 24 = 2 . 74 : 73
3x - 24 = 2 . 7
3x - 16 = 14
3x = 14 + 16
3x = 30
x = 30 : 3
x = 10
c) (x : 3 - 4) . 5 = 15
x : 3 - 4 = 15 : 5
x : 3 - 4 = 3
x : 3 = 3 + 4
x : 3 = 7
x = 7 . 3
x = 21
\(a,123-5.\left(x+4\right)=38\)
\(5.\left(x+4\right)=123-38=85\)
\(x+4=85:5=17\)
\(x=17-4=13\)
1) 7. (3x+5)+2.(7x+14)=98. 2) 4. (x -5)+3.(x+7)=22
3) 5.(4-x) +7.(x-2)=24. 4) 3.(x -5)+6.(x+3)=12
5) 4-x+5.(x+2)=38. 6) 5.( x-3)+2.(x+8)=22
7) 5.(x-7)+10.(4+x)=20. 8) 4.(x+10)+8.(x-3)=24
9) 4.(5-x)+5.(x-2)=15. 10) 4.(x-1)+3.(x-2)=-1
1) 2(x + 5) + 3(x + 7) = 41
2x + 10 + 3x + 21 = 41
5x + 31 = 41
5x = 10
x = 2
6) 7(x - 1) + 5(3 - x) = 11x - 10
7x - 7 + 15 - 5x = 11x - 10
2x + 8 = 11x - 10
-9x = -18
x = 2
2) 5(x + 6) + 2(x - 3) = 38
5x + 30 + 2x - 6 = 38
7x + 24 = 38
7x = 14
x = 2
7) 4(2 + x) + 3(x - 2) = 12
8 + 4x + 3x - 6 = 12
7x + 2 = 12
7x = 10
x = 10/7
3) 7(5 + x) + 2(x - 10) = 15
35 + 7x + 2x - 20 = 15
9x + 15 = 15
9x = 0
x = 0
8) 5(2 + x) + 4(3 - x) = 10x - 15
10 + 5x + 12 - 4x = 10x - 15
x + 22 = 10x - 15
9x = 37
x = 37/9
4) 3(x + 4) + (8 - 2x) = 22
3x + 12 + 8 - 2x = 22
x + 20 = 22
x = 2
9) 7(x - 2) + 5(3 - x) = 11x - 6
7x - 14 + 15 - 5x = 11x - 6
2x + 1 = 11x - 6
-9x = -7
x = 7/9
5) 4(x + 5) + 3(7 - x) = 49
4x + 20 + 21 - 3x = 49
x + 41 = 49
x = 8
10) 5(3 - x) + 5(x + 4) = 6 + 4x
15 - 5x + 5x + 20 = 6 + 4x
35 = 6 + 4x
4x = 29
x = 29/4
[ 8 x - 120 ÷ 4 ] ×3^3=3^6
123-5 (x+4)=38
(3x- 2^4)×7^3=2×7^4
\(\left[8x-120:4\right]\times3^3=3^6.\)
\(8x-120:4=3^3\)
\(8x-30=27\)
\(8x=27+30\)
\(8x=57\)
\(x=19\)
123 - 5.(x + 4) = 38
123 - 5x - 20 = 38
-5x = 38 - 123 + 20
-5x = -65
x = -65 : -5
x = 13
Vậy x = 13
\(123-5\left(x+4\right)=38\)
\(5\left(x+4\right)=123-38\)
\(5\left(x+4\right)=85\)
\(\left(x+4\right)=17\)
\(x=17-4\)
\(x=13\)
\(\left(3x-2^4\right)\times7^3=2\times7^4\)
\(\left(3x-2^4\right)=2\times7^4:7^3\)
\(\left(3x-2^4\right)=2\times7\)
\(3x-2^4=14\)
\(3x-16=14\)
\(3x=30\)
\(x=30:3\)
\(x=10\)
Bài 2. Tìm x biết:
a, 128 - 3(x + 4) = 23 d, 720 : [41 - (2x - 5)] = 2 3 .5
b, [(4x + 28).3 + 55] : 5 = 35 e, 123 – 5.( x + 4 ) = 38
c, (12x - 4 3 ).8 3 = 4.8 4 g, ( 3x – 2 4 ) .7 3 = 2.7 4
a,
128-3x-12=23
3x=128-12-23
3x=93
x=93:3
= 31
b,
(12x+84+55):5=35
12x+84+55=35.5
12x+84+55=175
12x=175-55-84
12x=36
x=36:12
x=3
Tìm số nguyên x, biết
a, 123 - 5 ( x + 4 ) = 38
b, ( 3x - 24 ) . 73 = 2 . 74
c, 5x+3 - 13 = 112
a, 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
b, ( 3x - 24 ) . 73 = 2 . 74
=> (3x-16).343=4802
=> 3x-16=4802:343
=>3x-16=14
=>3x=14+16
=>3x=30
=>x=30:3
=>x=10
c, 5x+3 - 13 = 112
=> 5x+3=112+13
=>5x+3=125
=> 5x+3=53
=> x+3=3
=>x=3-3
=>x=0
Tìm x
a 5(2x-3)-4(5x-7)=19-2(x+11)
b 7(4x+3)-4(x-1)=15(x+0,75)+7
c 3x-2,42+0,8x=3,38-0,2x
d (x-1)2+(x+3)2=2(x-2)(x+1)+38
e 5(x2-2x-1)+2(3x-2)=5(x+1)2
Tìm x
a 5(2x-3)-4(5x-7)=19-2(x+11)
b 7(4x+3)-4(x-1)=15(x+0,75)+7
c 3x-2,42+0,8x=3,38-0,2x
d (x-1)2+(x+3)2=2(x-2)(x+1)+38
e 5(x2-2x-1)+2(3x-2)=5(x+1)2
Tìm x
a 5(2x-3)-4(5x-7)=19-2(x+11)
b 7(4x+3)-4(x-1)=15(x+0,75)+7
c 3x-2,42+0,8x=3,38-0,2x
d (x-1)2+(x+3)2=2(x-2)(x+1)+38
e 5(x2-2x-1)+2(3x-2)=5(x+1)2
Tìm x
a 5(2x-3)-4(5x-7)=19-2(x+11)
b 7(4x+3)-4(x-1)=15(x+0,75)+7
c 3x-2,42+0,8x=3,38-0,2x
d (x-1)2+(x+3)2=2(x-2)(x+1)+38
e 5(x2-2x-1)+2(3x-2)=5(x+1)2