Answer:
3
Step-by-step explanation:
If we use pythagoras theorem we know a^2+b^2=c^2
c being the hypoeneuse
so we half the 8 to get the dimensions of the right angle so the bottom side is 4cm and then we use the hypotenuese which is 5 and plug it in so
a^2+4^2=5^2
a^2+16=25
-16 from both sides
a^2=9
square root both sides
a=3
