**2.3b Cari Hasil Tambah Punca (HTP) dan Cari Hasil Darab Punca (HDP) bagi suatu Persamaan Kuadratik**

**Contoh**

**:**

Cari hasil tambah punca dan hasil darab punca bagi persamaan yang berikut:

(a)

*x*^{2}+ 7*x*– 3 = 0(b)

*x*(*x*– 1) = 5 (1 –*x*)

*Penyelesaian:***(a)**

*x*

^{2}+ 7

*x*– 3 = 0

*a*= 1,

*b*= 7,

*c*= –3,

$\begin{array}{l}\text{HasilTambahPunca(HTP)}\\ \alpha +\beta =-\frac{b}{a}=-\frac{7}{1}=-7\\ \\ \text{HasilDarabPunca(HDP)}\\ \alpha \beta =\frac{c}{a}=-\frac{3}{1}=-3\end{array}$

**(b)**

*x*(

*x*– 1) = 5 (1 –

*x*)

*x*

^{2}–

*x =*5 – 5

*x*

*x*

^{2}–

*x*– 5 + 5

*x*= 0

*x*

^{2}+ 4

*x*– 5 = 0

*a*= 1,

*b*= 4,

*c*= –5,

$\begin{array}{l}\text{HasilTambahPunca(HTP)}\\ \alpha +\beta =-\frac{b}{a}=-\frac{4}{1}=-4\\ \\ \text{HasilDarabPunca(HDP)}\\ \alpha \beta =\frac{c}{a}=-\frac{5}{1}=-5\end{array}$