a = caiete
b = creioane
8a + 5b = 34
6a + 6b = 30
8 = 2³
6 = 2 • 3
cmmmc = 8 • 3 = 24
=>
{ 8a + 5b = 34 / • (3)
{ 6a + 6b = 30 / • (-4)
=>
{24a +15b = 102
{- 24a - 24b = -120
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\ -9b = - 18 => b = 2 lei
----------------------
24a + 15 • 2 = 102
24a + 30 = 102
24a = 72
a = 3 lei
----------------------
11a + 5b = 3 • 11 + 5 • 2 = 33 + 10 = 43 lei