tìm x
\(\frac{x+1}{2x+1}=\frac{0,5x+2}{x+3}\)
Tìm x , biết :
\(a,\frac{x+1}{2x+1}=\frac{0,5x+2}{x+3}\)
\(a)\) \(\frac{x+1}{2x+1}=\frac{0,5x+2}{x+3}\)
\(\Leftrightarrow\)\(\left(2x+1\right)\left(0,5x+2\right)=\left(x+1\right)\left(x+3\right)\)
\(\Leftrightarrow\)\(2x\left(0,5x+2\right)+0,5x+2=x\left(x+1\right)+3\left(x+1\right)\)
\(\Leftrightarrow\)\(x^2+4x+0,5+2=x^2+x+3x+3\)
\(\Leftrightarrow\)\(x^2+4x-x^2-4x=3-0,5-2\)
\(\Leftrightarrow\)\(0=0,5\) ( vô lí :'< )
Vậy không có x thoả mãn đề bài
Tìm x biết \(\frac{x+1}{2x+1}=\frac{0,5x+2}{x+3}\)
áp dụng tính chất của dãy tỉ số bằng nhau ta có:
\(\frac{x+1}{2x+1}=\frac{0,5+2}{x+3}=\frac{\left(x+1\right)-2.\left(0,5x+2\right)}{\left(2x+1\right)-2.\left(x+3\right)}=\frac{x+1-x-4}{2x+1-2x-6}=\frac{-3}{-5}=\frac{3}{5}\)
suy ra:
\(\frac{x+1}{2x+1}=\frac{3}{5}\Rightarrow5.\left(x+1\right)=3.\left(2x+1\right)\)
=>5x+5=6x+3
5x-6x=3-5
-x=-2
x=2
Tìm x , biết :
a\(\frac{x+1}{2x+1}=\frac{0,5x+2}{x+3}\)
\(\frac{x+1}{2x+1}=\frac{0,5x+2}{x+3}\)
\(\Rightarrow\left(x+1\right)\left(x+3\right)=\left(2x+1\right)\left(0,5x+2\right)\)
\(\Rightarrow x^2+3x+x+3=x+4x+0,5x+2\)
\(\Rightarrow x^2+3x+x-x-4x-0,5x=2-3\)
\(\Rightarrow x^2-x=-1\)
\(\Rightarrow x\left(x-1\right)=-1\)
:vvv
tìm x :
0,5x - 3/2x = 3\(0,5x-\frac{3}{2}x=\frac{2}{7}\)
tìm x:
/0,5x - 2/ - /x + \(\frac{2}{3}\)/=0
2x-/x+1/ = \(\frac{-1}{2}\)
Tìm x biết:
\(\frac{x^2}{6}=\frac{24}{25}\)\(\frac{x+1}{2x+1}=\frac{0,5x+2}{x+3}\)Tìm x
|10x +7 | < 37
|3 - 8x | nhỏ hơn hoặc bằng 19
| x +3| - 2x = | x- 4 |
\(\frac{3x+2}{5x+7}\)=\(\frac{3x-1}{5x+1}\)
\(\frac{x+1}{2x+1}\)=\(\frac{0,5x\cdot2}{x+3}\)
Tìm x :
\(\frac{x+1}{2x+1}=\frac{0,5x-2}{x-3}\)
Không tick không làm người :)
tim x biet
a;\(\frac{3x+2}{5x+7}=\frac{3x-1}{5x+1}\)
b; \(\frac{x+1}{2x+1}=\frac{0,5x+2}{x+3}\)
a) Ta có: \(\frac{3x+2}{5x+7}=\frac{3x-1}{5x+1}\)
\(\Leftrightarrow\left(3x+2\right)\left(5x+1\right)=\left(5x+7\right)\left(3x-1\right)\)
\(\Leftrightarrow3x\left(5x+1\right)+2\left(5x+1\right)=5x\left(3x-1\right)+7\left(3x-1\right)\)
\(\Leftrightarrow15x^2+3x+10x+2=15x^2-5x+21x-7\)
\(\Leftrightarrow15x^2-15x^2+3x+10x+5x-21x=-7-2\)
\(\Leftrightarrow-3x=-9\)
\(\Leftrightarrow x=3\)
Vậy x = 3
b) Ta có: \(\frac{x+1}{2x+1}=\frac{0,5x+2}{x+3}\Leftrightarrow\left(x+1\right)\left(x+3\right)=\left(2x+1\right)\left(0,5x+2\right)\)
\(\Leftrightarrow x\left(x+3\right)+\left(x+3\right)=2x\left(0,5x+2\right)+\left(0,5x+2\right)\)
\(\Leftrightarrow x^2+3x+x+3=x^2+4x+0,5x+2\)
\(\Leftrightarrow x^2-x^2+3x+x-4x-0,5x=2-3\)
\(\Leftrightarrow-0,5x=-1\Leftrightarrow x=2\)
Vậy x = 2