Answer:
6
Step-by-step explanation:
[tex] {(3 \sqrt{13}) }^{2} - {9}^{2} = {x}^{2} \\ 9(13) - 81 = {x}^{2} \\ 117 - 81 = {x}^{2} \\ 36 = {x}^{2} \\ x = 6
Use Pythagorean theorem
[tex]\\ \sf\longmapsto P^2=H^2-B^2[/tex]
[tex]\\ \sf\longmapsto P^2=(3√13)^2-9^2[/tex]
[tex]\\ \sf\longmapsto P^2=117-81[/tex]
[tex]\\ \sf\longmapsto P^2=36[/tex]
[tex]\\ \sf\longmapsto P=6[/tex]
