Răspuns:
Explicație pas cu pas:
a/5 = b/7
(a + 5)(b + 10) = (b + 1)(a + b)
ab + 10a + 5b + 50 = ab + b^2 + a + b
b^2 - 9a - 4b - 50 = 0
a = 5b/7
b^2 - 45b/7 - 4b - 50 = 0
b^2 - 45b/7 - 28b/7 - 50 = 0
b^2 - 73b/7 - 50 = 0
7b^2 - 73b - 350 = 0
= 5329 + 9800 = 15129 = 123^2
b1 = (73 + 123)/14 = 14
a1 = 5*14/7 = 10
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b2 = (73 - 123)/14 = -50/14 = -25/7
a2 = -5*25/7*7 = -125/49
