Triangle ABC had a perimeter 18 cm

Answer:
Use pythagoreum theorem to determine whether it is or isn't since I'm not really sure myself but here's my calculations.
Step-by-step explanation:
We need to find AC.
Picture a triangle called ABC. AB is one side and BC the other while AC is the hypotenuse.
AC=
[tex] ac = \sqrt{ab ^{2} + {bc}^{2} } \\ ac = \sqrt{ {7}^{2} } + {3}^{2} \\ ac = \sqrt{49 + 9} \\ ac = \sqrt{58 } \\ ac = 7.6 [/tex]
Round up the 7.6 to a whole number and you get AC=8. To get perimeter of a triangle simply add the sides together to get 18.
Not really sure about my answer but hope this helped.