Factor polynomials: quadratic methods (advanced)

Factor "advanced" polynomials (i.e. polynomials of various degrees and or with two variables) using quadratic factorization methods.

Problem

Factor the polynomial expression as the product of two binomials.
k, start superscript, 4, end superscript, minus, 9, k, start superscript, 2, end superscript, plus, 14, equals