Korzystamy z tw. Pitagorasa:
a² + b² = c²
gdzie:
a,b - przyprostkokątne,
c - przeciwprostokątna.
a)
[tex]x^{2}+6^{2} = 12^{2}\\\\x^{2} + 36 = 144\\\\x^{2} = 144 -36 = 108\\\\x = \sqrt{108} = \sqrt{36\cdot3}\\\\\boxed{x =6\sqrt{3}}[/tex]
b)
[tex]y^{2}+5^{2} = (3\sqrt{7})^{2}\\\\y^{2}+25 = 63\\\\y^{2} = 63-25 = 38\\\\\boxed{y = \sqrt{38}}[/tex]
