<=>\(\dfrac{7\left(x-3\right)}{7\left(x+5\right)}=\dfrac{5\left(x+5\right)}{7\left(x+5\right)}\)
<=>\(7\left(x-3\right)=5\left(x+5\right)\)
<=>\(7x-21=5x+25\)
<=>\(7x-5x=25+21\)
<=>\(2x=46\)
<=>\(x=\dfrac{46}{2}=23\)
a) 3/(x+2)(x+5) + 5/(x+5)(x+10) + 7/ (x+10)(x+7) = x/(x+2)(x+17)
tìm x
a, | 5/4x - 7/2 | - | 5/8x + 3/5 | = 0
b, 21/5 + 3 : | x/4 - 2/3 | = 6
c,| 9 + x | = 2x
d, | 2x - 3 | + x = 21
e, | 7 - 2x | + 7 = 2x
f, | -x + 2/5 | + 1/2 = 3,5
G, | 3x - 4 | + 4 = 3x
Tìm x
1; 5.| x + 2|= 10. (-2)
2; - 4| x - 2| = 8
3; 2. ( x - 5) - 3. ( x + 7) = 12
4; 7. ( 5 - x ) - 2. ( x + 3 ) = 15
Tìm x,biết:
1) |x+2| + |x-5| = 7
2) |x-7| + 2x+5 =6
3) |2x + 1| +|x+3| = 4x
4) |x2 -2x| = x
5) |2x+3| = x+2
6) |5x-4 |= |x+2|
7) |x-2| - |2x - 3| - x = 2
\(\dfrac{7^{x+2}+7^{x+1}+7^x}{57}=\dfrac{5^{2x}+5^{2x+1}+5^{2x+3}}{131}\)
tim x
1) Giá trị \(x\in Z\) để \(\frac{x-5}{7-x}\) là số hữu tỉ dương. x = ?
2) Cặp số nguyên dương chẵn x; y thỏa mãn biểu thức \(\frac{x}{2}+\frac{3}{7}=\frac{5}{4}\). Vậy x = .... ; y = ....
3) Giá trị \(A=\frac{\frac{2}{5}+\frac{2}{7}-\frac{2}{11}}{\frac{3}{5}+\frac{3}{7}-\frac{3}{11}}+\frac{\frac{1}{4}-\frac{1}{5}+\frac{1}{7}}{\frac{3}{4}-\frac{3}{5}+\frac{3}{4}}\)
Tìm x biết :
a) 5/6 + (2/3x- -7/12) = 1/2
b) x/15 + 1,2 = 1/3
c) 7/1 - 5/18 = -3/2
d) 3 + | x-1,34 | = 5
e) 5-|x+2,56|=3
Tìm x biết :
a) | 2x - 1 | = 4
b) -3 | 2x | + | 5 - x | = 1
c) 2^x + 3 = 2^x - 1 = 15/64
d) | -3 + 5 | = x
e) ( x - 1 )^100 + ( x - y )^98 = 0
f) ( x - 7 )^x + 1 - ( x - 7 )^x + 5 = 0
7*(x - 3) - 5*(3 - x) =11*x - 5
c)5^x+1-5^x=20 c)2^x+2^x+4=544 c)4^2x+1+4^2x=80 c)3^2x+2+3^2x+1=108 c)7^x+3-7^x+1=16464
