Question

Determinati nr x stiind ca a-b = 6 si ca x+3×a-3×b=20

Answer 1

x+3×(a-b)=20
x+3×6=20
x=20-18
x=2

Answer 2

a - b = 6  

x + 3 a - 3 b = 20

x + 3 × ( a - b ) = 20

x + 3 × 6 = 20

x + 18 = 20

x = 20 - 18

x = 2