Several vectors in the x-y plane are shown in the figure with their tails at the origin of the coordinate system and with a label at their heads. Two of these vectors are given in terms of the unit-vectors i and j as P = (2.80i + 2.30j) and Q = (-3.90i + 1.20j), where the numbers are measured in meters. Let M = (P+Q). Calculate the magnitude of the vector M.