In this activity, you will rearrange and solve a rational equation and find and use the inverse of a rational equation. As we’ve seen, for a circuit with two resistors arranged in parallel, we can calculate the total resistance in the circuit, RT , in ohms, with this equation.

1.Rewrite the equation to represent the resistance of resistor 2, R2 , in terms of RT and R1.

A. R2=RTR1/R1-1

B. R2= R1 + R2/RT R1

C. R2=RT - R1/RTR1

D. R2= RT R1/R1-RT

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The total resistance in a circuit with two parallel resistors is 2 ohms and R1 is 6 ohms.

Using the equation for R2, in terms of RT and R1, what is R2?

R2 is ? ohms

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2.Lightbulbs act as resistors. Janine is building a circuit that contains two lightbulbs in parallel. One of the lightbulbs has a resistance of 120 ohms, but the resistance of the second lightbulb is unknown. She models the total resistance in the circuit, t, with this equation, in which r represen