At a point in a machine member the stresses are σx (unknown), σy= -12 mpa and τxy=20 mpa. the allowable compressive stress at the point is 14 mpa. determine (a) the allowable tensile stress σx and (b) the principal & maximum shearing stresses in the member, orientations of principal & maximum shear planes. (c) sketch the mohr's circle representation of the state of stress and the maximum stress elements with orientations. (d) represent the stress tensors in matrix form.