Answer:
a=-4, b=-4. (-4, -4).
Step-by-step explanation:
-3a+7b=-16
-9a+5b=16
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-3(-3a+7b)=-3(-16)
-9a+5b=16
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9a-21b=48
-9a+5b=16
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-16b=64
b=64/-16
b=-4
-3a+7(-4)=-16
-3a-28=-16
-3a=-16+28
-3a=12
a=12/-3
a=-4
2*2*4+2*2*24+2*4*24
16+96+192=304
304 is the answer
Answer:
6 or 7
Step-by-step explanation:
If the half-life is t, then every t days, the amount of the radioactive isotope will be cut in half.
(1/2)^(number of half-lives) = 3%
number of half-lives = ln(0.03) / ln(0.5)
This gives the number of half-lives as 5.06.
Then 300 days = (5.06)(length of 1 half-life)
length of 1 half-life = 300 / 5.06 = 59.29 days
