Answer:
Pythagorean theorem formula is:
[tex]a {}^{2} + b {}^{2} = c {}^{2} [/tex]
Therefore:
[tex]16 {}^{2} + b {}^{2} = 34 {}^{2} \\ b {}^{2} = 34 {}^{2} - 16 {}^{2} \\ b {}^{2} = 1156 - 256 = \\ b {}^{2} = 900 \\ b = 30[/tex]