Tìm x :
a. x x 45 + x x 55 = 1000
b. 6 x + 1 2 = 2
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Tìm x:
a,x x 45 + x x 55 = 100
b, 6/x + 1/2 =2
Mình dùng dấu . thay cho dấu nhân nha
a) \(x.45+x.55=100\)
\(\Rightarrow x\left(45+55\right)=100\)
\(\Rightarrow x.100=100\Rightarrow x=1\)
b) \(\frac{6}{x}+\frac{1}{2}=2\)
\(\Rightarrow\frac{6}{x}=2-\frac{1}{2}\)
\(\Rightarrow\frac{6}{x}=\frac{5}{2}\)
\(\Rightarrow5.x=2.6=12\)
\(\Rightarrow x=\frac{12}{5}\)
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\(a,x\times45+x\times55=100\)
\(x\times\left(45+55\right)=100\)
\(x\times100=100\)
\(x=100\div100\)
\(x=1\)
\(b,\frac{6}{x}+\frac{1}{2}=2\)
\(\frac{6}{x}=2-\frac{1}{2}\)
\(\frac{6}{x}=\frac{3}{2}\)
\(\frac{6}{x}=\frac{6}{4}\)
\(x=4\)
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tìm x, biết :
a) 1/( x+1 ).( x+2 ) + 1/( x+2 ).( x+3 ) + 1/( x+3 ).( x+4 ) + ... + 1/( x+1999).( x+2000) = 1/x+200 = 1/5
b) 2/( x+1 ).( x+3 ) + 3/( x+3 ) .( x+6 ) + 4/( x+6 ).( x+10 ) + ... + 10/( x+45 ).( x+55 ) + 1/ x+55 = 1/6
tìm x biết
a)x-45/55+x-47/53=x-55/45+x-53/47
b)2-x/2002-1=1-x/2003-x/2004
c)x+2/98+x-4/96=x+6/94+x+8/92
d)x+1/9+x+2/8=x+3/7+x+4/6
mấy cái có x ở trên tử nhé
Tìm x:
a: 1/45+1/55+1/66+.....+2/x*(x+1)=1/9
b:1+1/3+1/6+1/10+.....+1/x*(x+1):2=3984/1993
Tìm x
X × 45 + x × 55 = 1000
6/x + 1/2 = 2
x . 45 + x . 55 = 1000
x . ( 45 + 55 ) = 1000
x . 100 = 1000
x = 1000 : 100
x = 10
Vậy x = 10
6 / x + 1 / 2 = 2
6 / x = 2 - 1 / 2
6 / x = 3 / 2
6 / x = 6 / 4
=> x = 4
Vậy x = 4
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x . 45 + x . 55 = 1000
x . ( 45 + 55 ) = 1000
x . 100 = 1000
x = 1000 : 100
x = 10
..............................................
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Xem thêm câu trả lời
Tìm x
a/ \(^{2^x}\). \(^{5^x}\) = 1000
b/ \(\dfrac{75^x}{25^x}\) = 81
tính:
1 + 3 + 6 + 10 +....+ 45 + 55/ 1 x 10 + 2 x 9 + 3 x 8 +...+ 8 x 3 + 9 x 2 + 10 x 1
a) \(\dfrac{x-45}{55}+\dfrac{x-47}{53}=\dfrac{x-55}{45}+\dfrac{x-53}{47}\)
b)\(\dfrac{x+1}{2004}+\dfrac{x+2}{2003}=\dfrac{x+3}{2002}+\dfrac{x+4}{2001}\)
a, \(\dfrac{x-45}{55}-1+\dfrac{x-47}{53}-1=\dfrac{x-55}{45}-1+\dfrac{x-53}{47}-1\)
\(\Leftrightarrow\dfrac{x-100}{55}+\dfrac{x-100}{53}=\dfrac{x-100}{45}+\dfrac{x-100}{47}\)
\(\Leftrightarrow\left(x-100\right)\left(\dfrac{1}{55}+\dfrac{1}{53}-\dfrac{1}{45}-\dfrac{1}{47}\ne0\right)=0\Leftrightarrow x=100\)
b, \(\dfrac{x+1}{2004}+1+\dfrac{x+2}{2003}+1=\dfrac{x+3}{2002}+1+\dfrac{x+4}{2001}+1\)
\(\Leftrightarrow\dfrac{x+2005}{2004}+\dfrac{x+2005}{2003}=\dfrac{x+2005}{2002}+\dfrac{x+2005}{2001}\)
\(\Leftrightarrow\left(x+2005\right)\left(\dfrac{1}{2004}+\dfrac{1}{2003}-\dfrac{1}{2002}-\dfrac{1}{2001}\ne0\right)=0\Leftrightarrow x=-2005\)
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a. lấy mỗi phân số e cộng vs 2 là bt làm ra liền
b, - 1 hoặc + 1 vs mỗi phân số nha
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Giải phương trình :
a, x-45/55 +x-47/53 =x-55/45 + x-53,47
b, x^2-10x-29/1971 +x^2-10x-27/1973 = x^2-10x-1971/29 + x^2-10x-1973/27
c, 2-x/2002-1= 1-x/2003 -x/2004
Các bạn giúp mik vs nhé !
a) \(\frac{x-45}{55}+\frac{x-47}{53}=\frac{x-55}{45}+\frac{x-53}{47}\)
\(\Leftrightarrow\left(\frac{x-45}{55}-1\right)+\left(\frac{x-47}{53}-1\right)=\left(\frac{x-55}{45}-1\right)+\left(\frac{x-53}{47}-1\right)\)
\(\Leftrightarrow\frac{x-100}{55}+\frac{x-100}{53}=\frac{x-100}{45}+\frac{x-100}{47}\)
\(\Leftrightarrow\frac{x-100}{55}+\frac{x-100}{53}-\frac{x-100}{45}-\frac{x-100}{47}=0\)
\(\Leftrightarrow\left(x-100\right)\left(\frac{1}{55}+\frac{1}{53}-\frac{1}{45}-\frac{1}{47}\right)=0\)
Vì \(\hept{\begin{cases}\frac{1}{55}< \frac{1}{45}\\\frac{1}{53}< \frac{1}{47}\end{cases}}\Rightarrow\frac{1}{55}+\frac{1}{53}-\frac{1}{45}-\frac{1}{47}< 0\)
\(\Rightarrow x-100=0\Rightarrow x=100\)
Vậy x = 100
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