Hola!
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{x + y = 75000
{y = x + 15000
Pour x:
x + x + 15000 = 75000
2x + 15000 = 75000
2x = 75000 - 15000
2x = 60000
x = 30000
Pour y:
y = 30000 + 15000
y = 45000
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{30000 + 45000 = 75000
{45000 = 30000 + 15000
{75000 = 75000
{75000 = 75000
[tex] \text{Bonne \: chance!}[/tex]