I am stuck on how to solve this problem. Any help is appreciated.

y = 2/7x - 1

Step-by-step explanation:

You are trying to put it in the form y = mx + b where m is the slope and b is the y-intercept.

To start, find the slope by doing change in y (between the two points) divided by change in x (between the two points). This would be:

3 - (-3) (change in y) / 14 - (-7) (change in x)

= 6/21

= 2/7

So the slope is 2/7.

Then, you have the equation y = 2/7x + b.

Since you know the point (14, 3) works, you know x = 14 and y = 3 is a solution to the equation. You can plug in those values which would be:

3 = 2/7 * 14 + b

3 = 4 + b

-1 = b

So that means the equation is y = 2/7x - 1

ending amount = beginning amount / (2^n)

where "n" = number of half-lives (or elapsed time / half-life)

ending amount = 50 mg / (2 ^10 / 5.3)

ending amount = 50 mg / (2 ^ 1.8867924528)

ending amount = 50 m / 3.6981210597

ending amount = 13.5203794557 mg

or about 13.5 mg remain

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