Question

2. 3x+4y = 14
x+5y = 12

Dikerjakan dengan tiga cara. yg bisa poin full

Answer 1

Verified answer

Eliminasi

3x + 4y = 14 (× 1)
x + 5y = 12 (× 3)
3x + ..4y = 14
3x + 15y = 36
--------------------- -
-11y = -22
y = -22/-11
y = 2

3x + 4y = 14 (× 5)
x + 5y = 12 (× 4)

15x + 20y = 70
..4x + 20y = 48
------------------------- -
11x = 22
x = 22/11
x = 2

jadi HPnya adalah {2 , 2}

substitusi

x + 5y = 12
x = 12 - 5y

3x + 4y = 14
3(12 - 5y) + 4y = 14
36 - 15y + 4y = 14
36 - 11y = 14
11y = 36 - 14
11y = 22
y = 22/11
y = 2

x = 12 - 5y
x = 12 - 5(2)
x = 12 - 10
x = 2

jadi HPnya adalah {2 , 2}

campuran

3x + 4y = 14 (× 1)
x + 5y = 12 (× 3)

3x +.. 4y = 14
3x + 15y = 36
---------------------- -
-11y = -22
y = -22/-11
y = 2

x + 5y = 12
x + 5(2) = 12
x + 10 = 12
x = 12 - 10
x = 2

jadi HPnya adalah {2 , 2}

Answer 2

Tu3x+4y=14 |× 1
x+5y=12 |×3

3x+4y=14. metode eliminasi
3x+15y=36
------------------- -
-11y= -22
y=-22/-11
y=2

3x+4y=14|5
x+5y=12|4

15 x+20y=70
4x+20y=48
-------------------- -
11x=22
x=22/11=2

x+5y=12
x= -5y+12

3x+4y=14
3(-5y+12)+4y=14
-15y+36+4y=14. metode substitusi
-11y+36=14
-11y=14-36
-11y=-22
y=-22/-11
y=2

x=-5y+12
x=-5(2)+12
x=-10-12
x=2

mohon di koreksi