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2 years ago

In ∆DEF, DE = 18, EF = 16, and DF = 12. Find m∠F.

Mathematics

1 answer:

german2 years ago

5 0

Answer:

∠F=78.58484226°

Step-by-step explanation:

a²=b²+c² - 2bc cosA

DE²=EF²+DF² - 2(EF)(DF)cos∠F

18²=16²+12²-2(16)(12)cos∠F

324=256+144-384cos∠F

324-400=-384cos∠F

76=384cos∠F

0.197916=cos∠F

∠F=cos⁻¹(0.197916)

∠F=78.58484226°

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2 years ago

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3 years ago

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Hello Shannonrodrigue. You can solve this by setting up an exponential growth equation.

$A = A_ob^t$
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Now we solve for b
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Now that we have found b, we can use the equation $A = 3000b^t$ to predict how many bacteria will be present after 10 hours.
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3 years ago

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