E.408. Dacă 5a+4b=955a+4b=955a+4b=95 și 2a+3b=45,2a+3b=45,2a+3b=45, calculați 11a+13b.11a+13b.11a+13b.
Răspuns: 230.230.230.
11a+13b=(5a+4b)+3⋅(2a+3b)=95+3⋅45=230.11a+13b = (5a+4b) + 3 \cdot (2a+3b) = 95 + 3 \cdot 45 = 230.11a+13b=(5a+4b)+3⋅(2a+3b)=95+3⋅45=230.