An equation means that two numbers on either side of the equals sign are equal to start with. Those two numbers are described by the two expressions. You have to keep them equal. You add, subtract, multiply or divide by the same number on both sides. You do whatever you need to do to get the unknown by itself on one side.
In this case,you might start by getting the constants on one side.
Subtract 2 so you get;
-3/P = -8/P - 5
add -8/P
5/P = -5
divide by 5
1/P = -1
multiply by P
1 = -P
multiply by -1
-1 = P
You might choose a different sequence of operations
In this case,you might start by getting the constants on one side.
Subtract 2 so you get;
-3/P = -8/P - 5
add -8/P
5/P = -5
divide by 5
1/P = -1
multiply by P
1 = -P
multiply by -1
-1 = P
You might choose a different sequence of operations