Question

Answer 1

\(b)3x(x+5)-2x-10=0\)

\(<=>3x(x+5)-2(x+5)=0\)

\(<=>(x+5)(3x-2)=0\) 

\(<=>\) \(\left[{}\begin{matrix}x+5=0\\3x-2=0\end{matrix}\right.< =>\left[{}\begin{matrix}x=-5\\x=\dfrac{2}{3}\end{matrix}\right.\)

Answer 2

a: =>x^2+8x+16-x^2+2x-3x+6=-13

=>7x+22=-13

=>7x=-35

=>x=-5

b: =>(x+5)(3x-2)=0

=>x=2/3 hoặc x=-5

Answer 3

a.

\(\Leftrightarrow x^2+8x+16-\left(x^2+x-6\right)=-13\)

\(\Leftrightarrow x^2+8x+16-x^2-x+6=-13\)

\(\Leftrightarrow7x=-35\)

\(\Leftrightarrow x=-5\)

b.

\(3x\left(x+5\right)-2x-10=0\)

\(\Leftrightarrow3x\left(x+5\right)-2\left(x+5\right)=0\)

\(\Leftrightarrow\left(x+5\right)\left(3x-2\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x+5=0\\3x-2=0\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x=-5\\x=\dfrac{2}{3}\end{matrix}\right.\)