Make a change of variable, x = Py, that transforms the following quadratic form into one with no cross-product terms. -10x-10x-10x-10x²+8x1x3+4x1x4+4x2x3 + 8x2x4 Construct P using the methods of Section 7.1. For the associated quadratic form, enter the eigenvalues in decreasing order (including multiplicities) into the answer box below, separated with commas.