First, let's draw each vector:
Since the vectors are perpendicular (the angle between then is 90°), we can use the Pythagorean theorem to find the magnitude of the resulting vector:
[tex]\begin{gathered} C^2=A^2+B^2 \\ C^2=4.5^2+5.2^2 \\ C^2=20.25+27.04 \\ C^2=47.29 \\ C=6.88 \end{gathered}[/tex]Therefore the magnitude of the sum of vectors is 6.88.