It looks like you had some of the numbers correct, but you just labeled it and rounded it incorrectly, and the teacher gave you super partial credit for it.
For my work, I'm assuming that side A is opposite of angle A and side B is opposite of angle B, etc...
Answer:
5cm in the diagram
Step-by-step explanation:
30/6=5
#1 √ 75
Answer : 5√3 or ≈ 8.66025
#2 √ 48
Answer : 4√3 or ≈ 6.9282
#3 √ 128
Answer : 8√2 or ≈ 11.31371
#4 √ 300
Answer : 10√3 or ≈ 17.32051
~~
#5 √⅔
Answer :

#6 √16/4
Answer : 2
#7 √ 6/8
Answer :

#8 √27/9
Answer : √ 2 or ≈ 1.73205
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I hope that helps you out!!
Any more questions, please feel free to ask me and I will gladly help you out!!
~Zoey
3x4x1/2= 6inches Multiply the base by the height and after multiply by one half