The given T is a linear transformation from R2 into R2. Show thatT is invertible and nd a formula for T_ 1 . T(x1,x2) 2 (4x1 8x2, 4x1 + 5x2] To show that T 's invertible, calculate the determinant of the standard matrix for T. The determinant of the standard matrix is (Simplify your answer.) 1 _ T (X1,X2] (Type an ordered pair. Type an expression using x1 and x2 as the variables.)