Respuesta :

Answer:

[tex]\sqrt{69}[/tex]

Step-by-step explanation:

from the pythagorean theorem:

[tex]a^2 + b^2 = c^2\\10^2 + b^2 = 13^2\\100 + b^2 = 169\\b^2 = 69\\b = \sqrt{69}[/tex]

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