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Calculate the measure of angle P:

Calculate the measure of angle P:-example-1
User John Lui
by
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1 Answer

3 votes

Answer:

122.3 degrees

Explanation:

To get the measure, we use the appropriate method

The method we are going to use here is the cosine rule

We have the general form as;

a^2 = b^2 + c^2 -2bc Cos A

where a = 25

b = 9 and c = 19

Substituting these values;

25^2 = 9^2 + 19^2 - 2(9)(19) Cos A

183 = -342 cos A

cos A = -183/342

cos A = -0.54

A = arc cos -0.54

A = 57.65 ( since cosine is negative in the second quadrant, then the value will be 180 - 57.65

= 122.35

User BofA
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2.8k points