Harga 3 kg jeruk sama dengab harga 2 kg apel.jika harga 2kg jeruk dah 1kg apel Rp70.000,00 maka uang yang harus dibayar tuti untuk membeli 5kg jeruk dan 3kg ape

3j - 2a = 0 ⇔ 3j = 2a
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3j - 2a = 0 | x 1 | 3j - 2a = 0
2j + a = 70.000 | x 2 | 4j + 2a = 140.000
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7j = 140.000
j = 140.000 : 7
j = 20.000

2j + a = 70.000
2(20.000) + a = 70.000
40.000 + a = 70.000
a = 70.000 - 40.000
a = 30.000

5j + 3a
5(20.000) + 3(30.000)
100.000 + 90.000
190.000

j :jeruk ; a : apel
3j=2a
Jika 2j + 1a = 70000
a = 70000-2j

3j = 2 (70000-2j)
3j = 140000 -4j
7j = 140000
j = 140.000/7
j = 20.000

a =70000-2 (20000)
a = 30000
Jadi, 5j+3a = 5(20000) + 3 (30000)
= 190000

Semoga mengerti,