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4 years ago

In △ABC, a=31, b=22, and c=18. Identify m∠A rounded to the nearest degree. HELP ME PLEASE!!

Mathematics

1 answer:

4vir4ik [10]4 years ago

3 0

Answer:

The measure of angle A is $101\°$

Step-by-step explanation:

we know that

Applying the law of cosines

$a^{2} =b^{2}+c^{2}-2(b)(c)cos(A)$

substitute the values and solve for cos(A)

$31^{2} =22^{2}+18^{2}-2(22)(18)cos(A)$

$cos(A)=[22^{2}+18^{2}-31^{2}]/(2(22)(18))\\ \\cos(A)=-0.193182\\ \\A=arccos(-0.193182)=101\°$

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A person 6 feet tall standing 18 feet away from a lamppost casts a 9 foot shadow. When the same person moves 4 feet farther from

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Answer:

<h2>12 feet 8 inch long cast a shadow</h2>

Step-by-step explanation:

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$x=\frac{22}{\sqrt{3}}$

$=12feet$ $8 inch$ answer

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sleet_krkn [62]

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