A page for randomness

Cramer’s Rule
Given a system of linear equations, Cramer’s Rule is a handy way to solve for just one of the variables without having to solve the whole system of equations. They don’t usually teach Cramer’s Rule this way, but this is supposed to be the point of the Rule. Instead of solving the whole system, you can use Cramer’s to solve for just one variable.

Look at the following system of equations:

2x y z = 3
x – y – z = 0
x 2y z = 0

Looking at the system, you have the left-hand side with the variables and the right-hand side with the answer values. Let D be the determinant of the coefficient matrix of the above system, and let Dx be the determinant formed by replacing the x-column values with the answer-column values.

Trackback This Post | Subscribe to the comments through RSS Feed