This video demonstrates how to solve a linear function with rational coefficients by multiplying by the reciprocal of the coefficient. The reciprocal is just a fancy way of saying the numerator and denominator are swapped. Two sample problems are solved using this method. Multiplying each side of the equation by the reciprocal of the rational coefficient of the variable 'x' is an allowed operation, but only because both sides are multiplies by the the same amount. The teacher then demonstrates how you can perform cancellation of the numerator and denominator terms with a common divisor to make the process of arriving at an answer much simpler. When doing problems like this, make sure to keep track of negative signs as you multiply both sides by the reciprocal.