1. The document is a math worksheet containing word problems to solve quadratic equations. It asks students to solve equations by factoring, completing the square, and using the quadratic formula. 2. Some example equations included x2 + 5x - 50 = 0, 2x2 + 3x + 1 = 0, and x2 - 15x + 30 = 0. 3. The last question asks students to determine the value of P such that the equation (p + 3)x3 + 3x - 4 = 0 has two equal roots.

1. Tugas 1
Matematika
NAMA KELOMPOK:
I GUSTI AGUNG PUTU WIDIANA PUTRA (7)
I PUTU SUKMA ARINDRA (5)
WAHYU DWIPAYANA LIMARTA (14)
I WAYAN ADI YASA (32)
SMK N 1 TABANAN
TH. PEL. 2013/2014

2. 1. Selesaikan persamaan kuadrat dibawah ini dengan cara memfaktorkan.
a.
b.
c.
d.
e.
X2 + 5X – 50 = 0
X2 + 3X = 0
X2 – 4 = 0
2X2 + 3X + 1 = 0
3X2 + 5X – 2 = 0
2. Selesaikan persamaan kuadratberikut ini dengan melengkapkan kuadrat sempurna.
a. X2 + 5X + 4 = 0
b. 2X2 – 14X + 12 = 0
3. Selesaikan persamaan kuadrat berikut ini dengan rumus ABC.
a. X2 – 15X + 30 = 0
b. X2 + 8X – 20 = 0
c. X2 + 3X = 0
4. Tentukan P agar persamaan kuadrat (p+3) x3 + 3X – 4 = 0 → mempunyai 2 akar sama.
JAWABAN :
1.a). x2 + 5x – 50 = 0
(x - 2) (x + 25) = 0
x -2 = 0
x = -1
b). x2 + 3x = 0
(x + 1) (x + 3)
atau
x + 25 = 0
x = -25

3. x +1 = 0
atau
x = -1
x+3=0
x = -3
c). x2 – 4 = 0
(x - 2) (x + 2)
x -2 = 0
atau
x=2
x +2 = 0
x = -2
d). 2x2 +3x + 1 = 0
(2x + 1) (x + 2)
2x + 1 = 0
atau
2x = 1
2x + 2 = 0
2x = 2
x=2
e). 3x2 + 5x – 2 = 0
(3x - 2) (3x + 3)
3x – 3 = 0
atau
3x = 3
3x + 3 = 0
3x = -3
= -1
2.a). x2 + 5x + 4 = 0
x2 + 5x + (1)2 = (-4) + (1)2
x2 + 5x + 1
= -3
(x - 4)2
= -3
x + 16
= -3
x
= -3 + 16
x
= 13

4. b). 2x2 – 14x + 12 = 0
2x2 – 14x
= -12
2x2 – 14x + (1)2 = (-12) + (1)2
2x2 – 14x + 1
= -12 + 1
2x2 – 14x + 1
= -11
(2x - 14)2
= -11
2x + 196
= -11
2x
= -11 – 196
3.a). x2 – 5x + 30 = 0
a = 1, b = -15, c = 30

5. X1 =
=
X2 =
=
b). x2 + 8x – 20 = 0
a = 1, b = 8, c = -20
=
=
=
X1 =
=
X2 =
=2
=
c). x2 + 3x = 0
a = 1, b = 3, c = 0
=
=
X1 =
=
= -8

6. X2 =
=
= -3
4.) (p + 3) x3 + 3x – 4 = 0