Determinants of 3x3 Matrices

Each of the problems below is a link. If you click on the problem, it will take you to a YouTube video of a full, step-by-step solution for the problem. You may try these problems as practice and use the videos to check your answer, or you can just watch the videos to see more worked-out example problems.

Find the determinant of the 3 by 3 matrix with elements 2, 1, 0, 0, negative 2, 4, 0, 1, and negative 3
Find the determinant of the 3 by 3 matrix with elements 1, 2, 5, negative 2, negative 3, 2, 3, 5, and 3
Find the determinant of the 3 by 3 matrix with elements 1, 0, 0, 0, 1, 0, 0, 0, and 1
Use a determinant to find the area of the triangle pictured here: triangle with vertices at left paren 2 comma 0 right paren, left paren 5 comma negative 2 right paren, and left paren 7 comma 3 right paren