What formula is used to calculate resistance in a circuit?

According to Ohm's Law, you can find the resistance (R) of a circuit by dividing the voltage (E) by the current (I). This comes from algebraically rearranging the primary formula E = I x R. If you use the Ohm's Law magic triangle (E on top, I and R on the bottom), you can cover up the R to see E positioned over I. This visually represents E divided by I. Options suggesting multiplication or addition are incorrect mathematical manipulations. Resistance is mathematically defined as the ratio of voltage to current.