2x - y = 7000 x + 2y = 1000 5x - 2y =.....? tolong di jawab sekarang
Matematika
neti10
Pertanyaan
2x - y = 7000 x + 2y = 1000 5x - 2y =.....? tolong di jawab sekarang
2 Jawaban
-
1. Jawaban oktavianiyosi
2x - y = 7000
x + 2y = 1000, x = 1000 - 2y
5x - 2y =.....?
2 (1000 - 2y) - y = 7000
2000 - 4y - y = 7000
2000 - 5y = 7000
- 5y = 5000
y = - 1000
x = 1000 - 2 (-1000)
x = 1000 + 2000
x = 3000
5x - 2y =.....?
5 (3000) - 2(-1000) = 15000 + 2000
= 17000 -
2. Jawaban rendyasnenck
2x - y = 7000
x + 2y = 1000
(dikali 2 setiap persamaan)
2x - y = 7000
2x + 4y = 2000
(dieliminasi)
-5y = 5000
y = 5000 : -5 = -1000
jadi, y = -1000
(ambil satu persamaan)
2x - y = 7000
(subtitusikan y = -1000)
Jadi, 2x - (-1000) = 7000
2x + 1000 = 7000
2x = 7000 - 1000
2x = 6000
x = 3000
jadi nilai x = 3000
nilai 5x - 2y = 5(3000) - 2(-1000) = 15000 - (-2000) = 15000 + 2000 = 17000