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Answer:
c=[tex]\sqrt{12}[/tex] or c=3.46410161514
Step-by-step explanation:
Use Pythagoras theorem: a²=b²+c², where a is the side opposite the right angle, and b and c are the other sides:
a²=b²+c²
4²=2²+c²
16=4+c²
c²=12
c=[tex]\sqrt{12}[/tex] or c=3.46410161514