Question

solve using the multiplication principle. don't forget to perform a check.
12x=-96
the solution is x=

Answer 1

The objective of the multiplication principle is to isolate the variable (x in this case) so that the coefficient of the variable is one (unity). Then the right hand side will be the value of x sought.
Typically, when both sides of the equation contain only one term, as is the case here, we would multiply both sides by the reciprocal of the coefficient of the variable, (1/12) in the present case to reduce the coefficient to one.
For
5x=15
we multiply both sides by the reciprocal of 5 to give
(1/5)*5x = (1/5)*15
x = 3
For more explanations and examples, see:
http://www.jamesbrennan.org/algebra/intro%20to%20algebra/multiplication_principle.htm

Answer 2

Thank you very much! Sike! Haha