This is a simple algebra question, where #p# is the variable we will try to discover. In order to do that, we must put all letters in one side of the equality and all numbers in the other. This can be done in two ways:
Apply the same operation to both sides of the equality, or send a number to the other side using the oposite operation.
#5p# is adding to the right side, so we will send it to the left side as a subtraction. Then, send the 3 the is adding on the left side as a subtracion to the right side:
Then subtract like terms;