
Using the property that if the equimultiples of corresponding elements of other rows (or columns) are added to every element of any row (or column) of a determinant, then the value of determinant remains the same
Using row transformation, R2 → R2- x R1

Using the property that if all elements of any row or column of a determinant are 0, then the value of determinant is 0.
Since R2 has all elements 0, therefore ∆ = 0.