**SPM Praktis (Soalan Panjang)**

**Soalan 1:**

Selesaikan persamaan kuadratik, (

*y*+ 3)(*y*– 4) = 30

*Penyelesaian:*(

*y*+ 3)(*y*– 4) = 30*y*

^{2}– 4

*y*+ 3

*y*– 12 = 30

*y*

^{2}–

*y*– 12 – 30 = 0

*y*

^{2}–

*y*– 42 = 0

(

*y*+ 6)(*y*– 7) = 0*y*+ 6 = 0,

*y*= –6

*y*– 7 = 0

*y*= 7

**Soalan 2:**

Selesaikan persamaan kuadratik, 5

*x*^{2}= 3(*x*– 2) + 8

*Penyelesaian:*5

*x*^{2}= 3(*x*– 2) + 85

*x*^{2}= 3*x*– 6 + 85

*x*^{2}– 3*x*– 2 = 0(5

*x*+ 2)(*x*– 1) = 05

*x*+ 2 = 0,*x*= $-\frac{2}{5}$Or

*x*– 1 = 0

*x*= 1

**Soalan 3:**

Selesaikan persamaan kuadratik, $\frac{2{p}^{2}-15}{p}=7$

*Penyelesaian:*2

*p*

^{2}– 15 = 7

*p*

2

*p*^{2}–7*p*– 15 = 0(2

*p*+ 3)(*p*– 5) = 02

*p*+ 3 = 0,*p*=*p*– 5 = 0

*p*= 5

**Soalan 4:**

Selesaikan persamaan kuadratik, $y\left(y-\frac{9}{2}\right)=\frac{5}{2}$

*Penyelesaian:*$\begin{array}{l}y\left(y-\frac{9}{2}\right)=\frac{5}{2}\\ {y}^{2}-\frac{9y}{2}=\frac{5}{2}\end{array}$

(×2), 2

(×2), 2

*y*^{2}– 9*y*= 52

*y*^{2}– 9*y*– 5 = 0(2

*y*+ 1)(*y*– 5) = 02

*y*+ 1 = 0,*y*= ½Or

*y*– 5 = 0

*y*= 5