1: \(3\sqrt{9}+\sqrt{\left(-1\right)^2}\)
\(=3\cdot3+1\)
=9+1
=10
2:
a: 
b: Để đường thẳng y=2x-6 song song với đường thẳng y=(2m-1)x+3 thì \(\left\{{}\begin{matrix}2m-1=2\\3\ne-6\left(đúng\right)\end{matrix}\right.\)
=>2m-1=2
=>2m=3
=>\(m=\dfrac{3}{2}\)
3:
ĐKXĐ: \(\left\{{}\begin{matrix}x>0\\x\ne1\end{matrix}\right.\)
\(A=\left(\dfrac{x-\sqrt{x}}{\sqrt[]{x}-1}-\dfrac{\sqrt{x}+1}{x+\sqrt{x}}\right):\dfrac{\sqrt{x}+1}{x}\)
\(=\left(\dfrac{\sqrt{x}\left(\sqrt{x}-1\right)}{\sqrt{x}-1}-\dfrac{\sqrt{x}+1}{\sqrt{x}\left(\sqrt{x}+1\right)}\right):\dfrac{\sqrt{x}+1}{x}\)
\(=\left(\sqrt{x}-\dfrac{1}{\sqrt{x}}\right)\cdot\dfrac{x}{\sqrt{x}+1}\)
\(=\dfrac{x-1}{\sqrt{x}+1}\cdot\dfrac{x}{\sqrt{x}}=\sqrt{x}\cdot\left(\sqrt{x}-1\right)\)
\(A=\sqrt{x}+35\)
=>\(x-\sqrt{x}-\sqrt{x}-35=0\)
=>\(x-2\sqrt{x}-35=0\)
=>\(\left(\sqrt{x}-7\right)\left(\sqrt{x}+5\right)=0\)
=>\(\sqrt{x}-7=0\)
=>x=49(nhận)
