Faktorisasi Persamaan Kuadrat

Bentuk $a x^{2} + b x = 0$

$\begin{aligned} a x^{2} + b x = 0 \\ x . (a x + b) = 0 \\ x = 0 atau a x + b = 0 \end{aligned}$

Bentuk $x^{2} - a^{2} = 0$

$\begin{aligned} x^{2} - a^{2} = 0 \\ (x + a) . (x - a) = 0 \\ x + a = 0 atau x - a = 0 \\ x = - a atau x = a \end{aligned}$

Bentuk $a x^{2} + b x + c = 0$

Lakukan cara trial and error (lihat contoh soal)

Contoh 01

$\begin{aligned} x^{2} - 5 x = 0 \\ x . (x - 5) = 0 \\ x = 0 atau x = 5 \end{aligned}$

Contoh 02

$\begin{aligned} x^{2} - 9 = 0 \\ x^{2} - 3^{2} = 0 \\ (x + 3) (x - 3) = 0 \\ x + 3 = 0 atau x - 3 = 0 \\ x = - 3 atau x = 3 \end{aligned}$

Contoh 03

$\begin{aligned} x^{2} + 3 x + 2 = 0 \\ (x + 2) (x + 1) = 0 \\ x + 2 = 0 atau x + 1 & = 0 \\ x = - 2 atau x = - 1 \end{aligned}$