Răspuns:
Explicație pas cu pas:
a/2 = b/7
a-b = 85
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a = 2b/7
2b/7 - ⁷⁾b = ⁷⁾85
2b-7b = 595 =>
-5b = 595 =>
b = 595:(-5) =>
b = -119 => a = b+85 =>
a = -119+85 => a = -34
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varianta II
a/2 = b/7
b-a = 85
a = 2b/7 =>
5b = 595 =>
b = 119 => a = b-85 =>
a = 119-85 => a = 34
