Explain the reasoning to your answer. Will mark you the Brainliest
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Answer:
6
Step-by-step explanation:
[tex]S_{n}[/tex] = [tex]\frac{a(1-r^{n}) }{1-r}[/tex]
63 = -3(1 - [tex]-2^{n}[/tex]) / (1- -2)
63 = (-3 + [tex]6^{n}[/tex])/3
63 = -1 + [tex]2^{n}[/tex]
64 = [tex]2^{n}[/tex]
n = 6