\(Bai1\)
\(a,2x^2+x=0\)
\(x.\left(2x+1\right)=0\)
\(\Rightarrow\left[{}\begin{matrix}x=0\\2x=-1\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x=0\\x=-\dfrac{1}{2}\end{matrix}\right.\)
\(b,2x\left(x-5\right)-x\left(3+2x\right)=26\)
\(2x^2-10x-3x-2x^2=26\)
\(\left(2x^2-2x^2\right)-\left(10x+3x\right)=26\)
\(-13x=26\)
\(-x=26:13\)
\(-x=2\)
\(x=2\)
\(Bai2\)
\(34^2+16^2+32.34=34^2+32.34+16^2=32^2+2.16.34+16^2=\left(34+16\right)^2=50^2=2500\)
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