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
Answer:
c
Step-by-step explanation:
We can solve this by setting up 2 equations. We can use any letters like. For now, I'll use x and y.
So now we know that x - y = 0.7 and x + y = 1.
Now we can eliminate one of the letters by adding or subtracting one equation from the other. I am going to eliminate y by adding the two together (the y and the -y cancel).
This gives us 2x = 1.7, and so x = 1.7 ÷ 2 = 0.85
Finally, we can substitute x for 0.85 back into one of the original equations to figure out what y equals. I'm going to use x + y = 1.
So now we have 0.85 + y = 1, so y = 1 - 0.85 = 0.15
The numbers, therefore, are 0.85 and 0.15 (you can check by using the other equation).
Hope this helps!
Answer:
2.5
Step-by-step explanation:
From the diagram, figure B was enlarged to obtain figure A.
The two figures are therefore similar.
The corresponding sides are in the same proportion. That constant value of the proportion is called scale factor.
It is given by:

Figure B is the image of A

Therefore the scale factor is 2.5
Answer:126
Step-by-step explanation: your welcome