Question

2x-3y = 18

x-4y = -2

berapa nilai x+y ?

--------------------------------------------
Menggunakan tahap eliminasi
-------------------------------------------

Answer 1

2x - 3y = 18 dikali 1 jadi 2x - 3y = 18
x - 4y = -2 dikali 2 jadi 2x - 8y = -4
terus dikurangi jadi
5y = 22
y = 22/5
y = 4,4
lalu disubtitusikan ke x - 4y = - 2
x - 4y = -2
x - 4.4,4 = -2
x - 17,6 = -2
x = -2 + 17,6
x = 15,6

x + y = 4,4 + 15,6 = 20

Answer 2

2x-3y=18 |×4|
x-4y=-2. |×3|

8x-12y=72
3x-12 y=-6
------------------- -
5x = 78
x =78/5

lalu kita subsitusikan
2x-3y=18
2(78/5)-3y=18
156/5 -3y=18
-3y= 18-156/5
-3y = -66/5
y= 22/5

hp:(78/5 , 22/5)

nilai x+y
=78/5+22/5
=78+22/5
=100/5
=20

semoga membantu