Question

\(x^2+3x-10=0\)

Answer 1

`x^2+3x-10=0`

`<=>x^2-2x+5x-10=0`

`<=>x(x-2)+5(x-2)=0`

`<=>(x-2)(x+5)=0`

`<=>` $\left[ \begin{array}{l}x=2\\x=-5\end{array} \right.$

Vậy `S={2,-5}`

Answer 2

\(x^2+3x-10=0\)

\(\Leftrightarrow x^2+5x-2x-10=0\)

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

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

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

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

\(S=\left\{-5,2\right\}\)

Answer 3

x^2+3x-10=0
<=>x^2 - 2x +5x-10=0
<=> x(x-2) + 5 (x-2)=0
<=> (x+5) (x-2)=0
<=> x+5=0 hoặc x-2=0
<=>x=-5 hoặc x=2

Vậy .............

Mình chúc bn hok tốt

Answer 4

\(x^2+3x-10=0\)

\(x^2+5x-2x-10=0\)

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

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

=>\(x+5=0=>x=-5\)

hoặc \(x-2=0=>x=2\)