Question

[Nguyễn Thanh Hiền]

Tìm x

1. /9-7x/=5x-3
2. 8x-/4x+1/=x+2
3. /17x-5/-/17x+5/=0
4. /3x+4/=2/2x-9/

Answer 1

[binhero chibi]

mình cũng đang bí bài này ai giúp với

Answer 2

[Thắm Đào]

1.\(\left|9-7x\right|=5x-3\)

\(\Leftrightarrow\orbr{\begin{cases}9-7x=5x-3\\9-7x=-5x-3\end{cases}}\)

\(\Leftrightarrow\orbr{\begin{cases}-7x-5x=-9-3\\-7x+5x=-9-3\end{cases}}\)

\(\Leftrightarrow\orbr{\begin{cases}-12x=-12\\-2x=-12\end{cases}}\)

\(\Leftrightarrow\orbr{\begin{cases}x=-12:\left(-12\right)\\x=-12:\left(-2\right)\end{cases}}\)

\(\Leftrightarrow\orbr{\begin{cases}x=1\\x=6\end{cases}}\)

2.\(8x-\left|4x+1\right|=x+2\)

\(\Rightarrow\left|4x+1\right|=8x-x+2\)

\(\Rightarrow\left|4x+1\right|=7x+2\)

\(\Leftrightarrow\orbr{\begin{cases}4x+1=7x+2\\4x+1=-7x+2\end{cases}}\)

\(\Leftrightarrow\orbr{\begin{cases}4x-7x=2-1\\4x+7x=2-1\end{cases}}\)

\(\Leftrightarrow\orbr{\begin{cases}-3x=1\\11x=1\end{cases}}\)

\(\Leftrightarrow\orbr{\begin{cases}x=1:\left(-3\right)\\x=1:11\end{cases}}\)

\(\Leftrightarrow\orbr{\begin{cases}x=\frac{-1}{3}\\x=\frac{1}{11}\end{cases}}\)