To model half-life, use the formula

. Here,

is the amount remaining after a length of time

.

is the amount that you start with.

is the half-life. You plug in 50 for

, 10 for

, and 25 for

. You get

.
8. 3x-4>38
3x>38+4
3x>42
x>42/3
x>14
So the answer is A. x>14
9. It's A. Two less than four times a number is 12. Because 4x (four times) and also it says 2 less than 4 times a number...
Answer:just do the math mate
Step-by-step explanation:
You can use a tangent:

We have opposite = 17 and adjacent = x.

substitute:
cross multiply
multiply both sides by √3

divide both sides by 3

Use the Pythagorean theorem:

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Other method.
triangle.
The sides are in the ratio 
Therefore

Current value of the boat = $45000
Rate at which the value decrease = 8.5%
Value decreased after 1 year = 
Hence, value becomes = 
Value decreased after 2nd year =

Hence, value becomes = 
Value decreased after 3 year =

Hence, value becomes = 
So, value of the boat after 3 years becomes $34472.74