If the 2 is little and on top of the a, then it's called "nine a squared."
Answer:
the first one
Step-by-step explanation:
In the other 2 i can see the x repeats itself meaning it isn't a function.
C=10, C=90°, B=30°, A+B+C=180°
A+30°+90°=180°⇒A=60°
cos30°=a/c
cos30°=a/10⇒a=cos30°*10
a<span>≃8.6602
c²=a²+b²⇒b²=c²-a²
b²=10²-8.6602²⇒b²=25
b=5
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