The subject of a formula
The subject of a formula is the variable at the front of the equal signed which all the other numbers and operations equal to. For example, in the following formula, V is the subject.
V = IR
Changing the subject of the formula
When changing the subject of the formula, the formula will need to be rearranged. For example, to make I the subject the following steps are taken.
V = IR (divide both sides with R)
= I (flip the sides to make I the subject on the left hand side