Which ordered pair is a solution of inequalities?
{ y > -2
{x + y < _ 4
a) (-2,-3)
b) (1,3)
c) (1,5)
d) (0,-4)

B is the only solution

Step-by-step explanation:

These inequalities are shown in the attached picture. Which can be obtained drawing y > -2 (an horizontal line at y=-2, the region is above). and y<= 4-x, a line with a negative slope of -1 and intercept point of 4.

Any ordered pair, located inside the interception between these two regions is a solution of the system.

A. is Outside, below the horizontal line

B. is not clear by graph, hence, lets evaluate it in both inequalities

3>-2 (satisfies)

1+3<=4 (satisfies)

Hence B is a solution.

C. Is outside, we can evaluate it just to make sure:

5>-2 (satisfies)

1+5<= 4 (not true)

Hence C is not a solution.

D. is outside

yes

step-by-step explanation:

yes

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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