1. TUGAS 2
1. a. x2 + 5x – 50 = 0
x2 + 10x – 5x = 50 = 0
x(x + 10) – 5 (x + 10)
(x – 5) (x + 10)
b. x2 + 3x = 0
x(x + 3)
(X + 0) (X +3)
c. x2– 4 = 0
x2 – 22
(x + 2) (x – 2)
d. 2x2 + 3x + 1 = 0
2x2 + 2x + 1x + 1 = 0
2x(x + 1) + 1(x + 1)
(2x + 1) (x + 1)
e. 3x2 + 5x – 2= 0
3x2 + 6x – 1x – 2 = 0
3x(x + 2) – 1(x + 2)
(3x – 1) (x + 2)
2. a. x 2 + 5x +4 = 0
X2 + 5 X = -4
x2 + 5 x + ( .5)2 = -4 + (2,5)2
x2 + 5 x + (2,5)2
= -4 + (2,5)2
x2 + 5 x + 6,25
= -4 + 6,25
x2 + 5 x + 6,25 = 2,25
(x + 2,5 )2 = 2,25
X + 2,5 =
X + 2,5 = 1,5

2. x = 1,5 – 2,5
x=-1
atau
x + 2,5
= - 1,5
x
= - 1,5 – 2,5
x
=-4
b. 2x 2 – 14x + 12 = 0
x2 – 7x + 6 = 0
x2 = 7x = -6
x2 – 7x + ( . 7 )2 = -6 + ( . 7 )2
x2 – 7x + (3,5)2 = -6 + (3,5)2
x2 – 7x + 12,25 = -6 + 12,25
(x – 3,5)2 = 6,25
X – 3,5 =
X = 3,5 = 2,5
X = 2,5 + 3,5
X=6
Atau
X = 3,5 = - 2,5
X = -2,5 + 3,5
X=1
3. a. x2 – 15x + 30 = 0 a = 1 , b = -15 , c = 30
x12=
=
=
=

3. b. x2+ 8x + 20 = 0
a = 1 , b = 8 , c = 20
x12 =
=
= -4
= -4
-4
c. x2 + 3x = 0
x12 =
=
=
4. (p+3)x 2 + 3x - 4 = 0
D = b2 – 4ac
D = 32 – 4. ( p + 3 ) = 0
D = 9 +16 ( p + 3 ) = 0
D = 9 + 16 p + 48 = 0
D = 16 p + 48 + 9 = 0
D = 16 p + 57
=0
16 p + 57
=0
P = 57
16
a=1,b=3,c=0