Answer:
13
Step-by-step explanation:
To get the hypotenuse (the longest side) you would use the Pythagorean Theorem ([tex]a^{2} + b^{2} = c^{2}[/tex])
Replace a and b with the two given sides and solve for c
[tex]5^{2} + 12^{2} = c^{2}[/tex]
25 + 144 = [tex]c^{2}[/tex]
169 = [tex]c^{2}[/tex]
Find the square root of both sides
[tex]\sqrt{169} = \sqrt{c^{2}}[/tex]
13 = c
