Question

Rapid Pls!! Imi trebuie maine!

Answer 1

a) a + b = 20 |×3
b + c = 30 |×4

3×a + 3×b = 60
4×b + 4×c = 120
___________ adunam cele doua relatii

3×a + 7×b + 4×c = 60 + 120 = 180



b) a + b = 33
a + c = 11

5 × a + 3 ×b + 2 × c =

3×a + 3×b + 2× a + 2×c =

3 × (a + b) + 2 × (a + c) =

3 × 33 + 2 × 11 =

99 + 22 =

121
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