Solve R1 in Rt = R3 + [ ( 1/R1 + 1/R2 ) ^-1 ] for Parallel Circuits

[aks333]

Homework Statement

Rearrange formula for series and parallel circuit combination.
Make R1 the subject of the formula : Rt = R3 + [ ( 1/R1 + 1/R2 ) ^-1 ]

Homework Equations

Rt = R3 + [ ( 1/R1 + 1/R2 ) ^-1 ]

The Attempt at a Solution

I am unsure as to how to get rid of the inverse? please help.

 

[gneill]

Rt = R3 + ( 1/R1 + 1/R2 )^-1

Rt - R3 = ( 1/R1 + 1/R2 )^-1

1/(Rt - R3) = 1/R1 + 1/R2

Continue...