Step-by-step explanation:
P(t) = 12,000 (2)^(-t/15)
9,000 = 12,000 (2)^(-t/15)
0.75 = 2^(-t/15)
ln(0.75) = ln(2^(-t/15))
ln(0.75) = (-t/15) ln(2)
-15 ln(0.75) / ln(2) = t
t = 6.23
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The greatest common factor (GCF) of 48 and 78 is: 6
Factors of 48: 1, 2, 3, 4, 6, 8, 12, 16, 24, 48
Factors of 78: 1, 2, 3, 6, 13, 26, 39
The common factors between the two numbers are 1, 2, 3, and 6, but considering 6 is the highest number out of them, it is the greatest common factor.
Is that a question or answer? If it's a question that's the right answer.
Standard form is y=mx+b
y=9x+4