Divide 3 1/2 by 7= 1/2 a cup per person
Cheetah: 3 hours
Antelope: 5 hours
Lion: 6 hours
Elephant: 10 hours
Tan(12)=-0.6358599287. That means -0.6358599287 = 10/x so you can swap the x to the other side to make x = 10/-0.6358599287 Which equals -15.7 rounded to the nearest tenth.
Answer: 
<u>Add 3x to both sides</u>
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<u>Subtract 15 from both sides</u>
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<u>Divide both sides by 5</u>
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