👤

(a:b+639:3)×2=2×5×75
iar a=648​


Răspuns :

Salutare!

(648:b+639:3)×2=2×5×75

(648:b+213)×2=10×75

(648:b+213)×2=750

(648:b+213)=750:2

648:b+213=375

648:b=375-213

648:b=162

b=648:162

b=4