Răspuns :
Răspuns:
Explicație pas cu pas:
a + b + c = 180
a + 2 × c = 130
____________ adun sumele
2 × a + b + 3 × c = 310 l × 2
_____________________
4 × a + 2 × b + 6 × c = 2 × 310
4 × a + 2 × b + 6 × c = 620
a + b + c = 180
a + 2 × c = 130
a + b + c + a + 2 × c =
2 × a + b + 3 × c = 180 + 130
2 × a + b + 3 × c = 310 | × 2
4 × a + 2 × b + 6 × c = 620
a + 2 × c = 130
a + b + c + a + 2 × c =
2 × a + b + 3 × c = 180 + 130
2 × a + b + 3 × c = 310 | × 2
4 × a + 2 × b + 6 × c = 620