Bài làm :
\(a\text{)}...\Leftrightarrow\orbr{\begin{cases}x\div7-7=0\\x.3-12=0\end{cases}}\Leftrightarrow\orbr{\begin{cases}x\div7=7\\x.3=12\end{cases}}\Leftrightarrow\orbr{\begin{cases}x=49\\x=4\end{cases}}\)
\(b\text{)}\Leftrightarrow...\Leftrightarrow x\div2=15\Leftrightarrow x=15.2=30\)
\(c\text{)}...\Leftrightarrow100\div x=20\Leftrightarrow x=100\div20=5\)
\(d\text{)}...\Leftrightarrow x\div5=27\Leftrightarrow x=27.5=135\)
Tìm x, biết:
a) (x - 7):5 = 0;
b) x : 3 - 13 = 47
c) (x : 7 - 7) (x: 12 - 12) = 0;
d) 135 + x : 2 = 150
e) 140 - 100 : x = 120;
g) 300 - x : 5 = 273.
Tìm x, biết:
a) (x - 7):5 = 0; b) x : 3 - 13 = 47
c) (x : 7 - 7) (x: 12 - 12) = 0; d) 135 + x : 2 = 150
e) 140 - 100 : x = 120; g) 300 - x : 5 = 273
a, ( x-7 ) : 5 = 0
b, ( x:7-7 )( x:12-12) = 0
c, 300 - x : 5 = 273
d, 135 + x : 2 = 150
a) (x-5).2=0
b) x.3-13=47
c) (x.7-7)(x.12+24)=0
d) 135=x.2=151
e) 140-10.x=120
g) x.5-127=273
tính nhanh :
3 + 5 + 7 + 9 +...+ 51
Tìm x :
a ) 135 + x . 2 = 151
b ) x . 5 - 227 = 273
c ) ( x - 4 ) . 3 + 2 = 101
d ) 170 - ( 4 + 5 . x ) = 101
GIUP TỚ
Tìm x∈Z, biết:
a)x.(x-6)=0
b)(-7-x).(-x+5)=0
c)(x+3).(x-7)=0
d)(x-3).(x2+12)=0
e)(x+1).(2-x) ≥0
f)(x-3).(x-5) ≤0
1. Tìm x, biết :
a) ( x : 7- 7 ) ( x : 12 - 12 ) = 0 b) 140 - 100 : x = 120
c) 300 - x : 5 = 273 d) 300 - x : 5 = 273
e) ( x : 2 - 2 ) ( x : 3 - 3 ) = 0 f) 58 - x : 18 = 52
g) 214 - 136 : x = 197 h) ( x - 5 ) : 3 = 0
2. Tìm x, biết :
a) ( x - 3.5 ) . 12 = 0 b) 35. ( x - 10 ) = 35
c) ( x - 5 ) : 3 + 3 = 24 d) ( x - 4 ) : 3 - 2 = 100
3. Tìm x, biết :
a) ( x - 5.9 ) . 2 = 0 b) 21. (32 - x ) = 21
c) 25. ( 2. x - 4) . 12 = 0 d) ( x - 4 ) : 6 - 5 = 10
giai giup mik nha:
Bài 1 Tìm x
1.3/4:x/6=75/100
2.(1/4*x-1/8)*3/4-1/4
3.71+65*4=x+140/x +260
4.7878:(12*x-91)=78
5.2/7+3/7<x<14/5+7/5
6.(x+1)+(x+4)+(x+7)+(x+10)+....+(x+34)=330
7.96-3,75:x=94,5
8.(7*13+8*13):(29/3-x)=39
Lưu ý:câu3 có nghĩa là x+140 trên x rồi +260
giai giup mik nha:
Bài 1 Tìm x
1.3/4:x/6=75/100
2.(1/4*x-1/8)*3/4-1/4
3.71+65*4=x+140/x +260
4.7878:(12*x-91)=78
5.2/7+3/7<x<14/5+7/5
6.(x+1)+(x+4)+(x+7)+(x+10)+....+(x+34)=330
7.96-3,75:x=94,5
8.(7*13+8*13):(29/3-x)=39
Lưu ý:câu3 có nghĩa là x+140 trên x rồi +260
