Tìm x\(\in\) Q : \(\frac{x}{4}=\frac{9}{12}\)
Tìm x, y \(\in\) Z
a) \(\frac{-11}{12}< \frac{x}{12}< \frac{-3}{4}\)
b) \(\frac{1}{18}< \frac{x}{12}< \frac{y}{9}< \frac{1}{4}\)
Ai làm rõ ràng và đúng mk tick
\(a)\) \(\frac{-11}{12}< \frac{x}{12}< \frac{-3}{4}\)
\(\Leftrightarrow\)\(\frac{-11}{12}< \frac{x}{12}< \frac{-9}{12}\)
\(\Leftrightarrow\)\(-11< x< -9\)
\(\Rightarrow\)\(x=-10\)
Tìm x, y
\(\frac{x+4}{y+6}=\frac{2}{3}\) và y - x = 12
\(\frac{x}{3}-\frac{9}{y}=\frac{5}{12}\left(x,y\in N\right)\)
Tìm x \(\in\) Z
\(\frac{1}{-2}+\frac{1}{+}+\frac{-6}{9}\le x\le\left(\frac{1}{4}+\frac{-5}{13}\right)+\left(\frac{3}{6}+\frac{8}{-13}+\frac{9}{12}\right)\)
Tìm x, y biết
a, y = \(\frac{x^4-2x^3+1}{x^2+1}\)với x,y \(\in\)Z
b, y =\(\frac{x+1}{x^2+1}\)với x,y \(\in\)Z
c, 3x + 4y - xy = 15
d, (x + 1)(2y - 1) = 12
e, \(\frac{1}{18}< \frac{x}{12}< \frac{y}{9}< \frac{1}{4}\)với x,y \(\in\)Z
g, \(\frac{3}{x-5}=\frac{-4}{x+2}\)
Tìm x, y \(\in Z\)
\(\frac{1}{18}< \frac{x}{12}< \frac{y}{9}< \frac{1}{4}\)
Ai làm đúng và rõ ràng, mk tick
Có 1/18 < x/12 < y/9 < 1/4
Suy ra 2/36 < 3x/36 < 4y/36 < 9/36
Suy ra 2 < 3x < 4y < 9
Suy ra 3x=6 Suy ra x=2
Suy ra 4y=8 Suy ra y=2
\(\Leftrightarrow\frac{2}{26}< \frac{3x}{36}< \frac{4y}{36}< \frac{1}{4}\)
=> 2 < 3x < 4y < 9
\(\Rightarrow\hept{\begin{cases}2< 3x< 9\\2< 4y< 9\\3x< 4y\end{cases}\Rightarrow\hept{\begin{cases}x=2\\y=2\end{cases}}\left(\text{th}ỏa\text{ m}ãn\right)}\)
=> x = 2; y = 2
\(\frac{1}{8}< \frac{x}{12}< \frac{y}{9}< \frac{1}{4}\)
<=> \(\frac{2}{36}< \frac{3x}{36}< \frac{4x}{36}< \frac{1}{4}\)
=> 2<3x<4y<9
<=>\(\hept{\begin{cases}2< 3x< 9\\2< 4x< 9\\3x< 4y\end{cases}}< =>\hept{\begin{cases}x=4\\y=2\end{cases}}\)
vậy giá trị x=2 và y=2 thỏa mãn
Tìm \(x,y\in Z\) biết:
\(\frac{1}{18}+\frac{x}{12}+\frac{y}{9}+\frac{1}{4}\)
thánh nk nhanh con tick cho nha
Câu 1:Tìm x
\(\frac{x}{12}=\frac{3}{8}.\frac{7}{9};\)\(\frac{7}{x}=\frac{7}{12}.\frac{9}{2}\)
Câu 2:Tính nhanh
\(\frac{4}{25.27}+\frac{4}{27.29}+\frac{4}{29.31}+......+\frac{4}{49.51}\)
\(\frac{1}{25.27}+\frac{1}{27.29}+........+\frac{1}{49.51}\)
Tìm x;
\(\frac{x+4}{12}=\frac{3}{9}\)
\(\frac{x+4}{12}=\frac{3}{9}\)
\(\Leftrightarrow\frac{x+4}{12}=\frac{1}{3}\)
\(\Leftrightarrow3\left(x+4\right)=12\)
\(\Leftrightarrow3x+12=12\)
\(\Leftrightarrow3x=0\)
\(\Leftrightarrow x=0\)
\(\Rightarrow9\left(x+4\right)=3.12\)
\(\Rightarrow9x+36=36\)
\(\Rightarrow9x=0\)
\(\Rightarrow x=0\)
\(\frac{x+4}{12}=\frac{3}{9}\)
\(\Leftrightarrow\left(x+4\right)9=36\)
\(\Leftrightarrow9x+36=36\)
\(\Leftrightarrow9x=0\)
\(\Leftrightarrow x=0\)
a) Tìm số nguyên x, biết:
\(\frac{x}{9}=\frac{-12}{27}\)
b) Tìm số nguyên x, biết: 12 - ( x - 4 ) = 17
c) Tìm y biết: \(\left(1\frac{2}{3}+2\frac{2}{3}y\right).\frac{10}{11}=2\frac{3}{11}\)
a) Ta có: \(\frac{x}{9}=\frac{-12}{27}\)
=> \(27.x=-12.9\)
=> \(27x=-108\)
=> \(x=108:27\)
=>\(x=4\)