# Question: What is the formula for determinants?

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The determinant is: |A| = ad − bc or the determinant of A equals a × d minus b × c. It is easy to remember when you think of a cross, where blue is positive that goes diagonally from left to right and red is negative that goes diagonally from right to left.

## How do you use the determinant formula?

Solve a system of two equations using Cramers rule.Evaluate the determinant D, using the coefficients of the variables.Evaluate the determinant. D x . Evaluate the determinant. D y . Find x and y. Write the solution as an ordered pair.Check that the ordered pair is a solution to both original equations.6 May 2020

## Why do we calculate determinants?

The determinant is useful for solving linear equations, capturing how linear transformation change area or volume, and changing variables in integrals. The determinant can be viewed as a function whose input is a square matrix and whose output is a number.

If we multiply a scalar to a matrix A, then the value of the determinant will change by a factor ! If two determinants differ by just one column, we can add them together by just adding up these two columns.