X+2y=122 dan 2x+y =130 maka nilai x tambah y adalah

Kelas 8 Matematika
Bab SPLDV

x + 2y = 122
x = 122 - 2y

2x + y = 130
2 (122 - 2y) + y = 130
244 - 4y + y = 130
-3y = 130 - 244
y = -114/-3
y = 38

x = 122 - 2y
x = 122 - 2 . 38
x = 122 - 76
x = 46

x + y
= 46 + 38
= 84

Mapel : Matematika
Materi : Persamaan Linear

x + 2y = 122
x = 122 - 2y
---------

2x + y = 130
2(122 - 2y) + y = 130
244 - 4y + y = 130
3y = 244 - 130
3y = 114
y = 114/3
y = 38

x = 122 - 2y
x = 122 - 2(38)
x = 122 - 76
x = 46

⇔ x + y
⇔ 46 + 38
⇔ 84