Determine if the following sets are subspaces of R n×n under the usual operations.

(a) The set of all upper triangular matrices.

(b) The set of all symmetric matrices.

(c) The set of all orthogonal matrices.

(d) The set of all matrices A such that A2 = 0.​

Four equations are shown below.equation 1: y=2*equation 2: y=2x-5equation 3: y=x2 + 6equation 4: tdentify one linear equation and one nonlinear equation from the list.why each equation you identified is linear or nonlinear.nd one nonlinear equation from the list. state a reasonlinear equation