Use kirchhoff's rules to determine the value of current `I_(1)` flowing in the circuit

Answer

`- 0.75 A`

Explanation

According to kirchhoff's junction rule `l_(3) = l_(1) + l_(2)`
According to kirchhoff's loop rule .For loop `FEDCF`
`30l_(1) = 20l_(3) = 20`
`30l_(1) + 20(l_(1) + l_(2))= 20`
or`30l_(1) + 20l_(1) = 20 or 5l_(1) + 2l_(2) = 2`…..(i)
For loop `AFEDCBA`
`30 l_(1) - 20 l_(2) = -80`
or `2l_(2) - 3 l_(1) = 8 `....(ii)
Subtraching (ii) from (i) we get
`8 l_(1) = - 6 or l_(1) = - 6//8 = - 0.75 A`