Pretty easy middle school math

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

step-by-step explanation:

the first 5 right here the next 5 i will upload as separate question