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In 6 years, Jonathan's age will be twice Alfredo's age. What is Jonathan's current age if three years ago he was three times Alfredo's age?

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Answer to a math question In 6 years, Jonathan's age will be twice Alfredo's age. What is Jonathan's current age if three years ago he was three times Alfredo's age?

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Jett
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97 Answers
\begin{cases} x + 6 = 2(y + 6) \\x - 3 = 3(y - 3) \end{cases}

1. De la primera ecuación:
x + 6 = 2y + 12
x - 2y = 6

2. De la segunda ecuación:
x - 3 = 3y - 9
x - 3y = -6

3. Resolvamos el sistema de ecuaciones

Restando las dos ecuaciones:
(x - 2y) - (x - 3y) = 6 - (-6)
y = 12

4. Sustituyamos y = 12 en una de las ecuaciones para encontrar x :
x - 2y = 6
x - 2(12) = 6
x - 24 = 6
x = 30

Por lo tanto, la edad actual de Jonathan es:
x = 15 \, años

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