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Help me with number 3 pleaseeeeeeeeeee!!!!!!!!!!!!!!!!!

Help me with number 3 pleaseeeeeeeeeee!!!!!!!!!!!!!!!!!-example-1
User Jacmkno
by
3.4k points

1 Answer

6 votes

Given:

∠M = 0.775 radians, m = 5 ft, n = 7 ft, p = 4 ft

To find:

The measure of angle P.

Solution:

Using law of cosine:


p^2=m^2+n^2-2mn \cos P

Substitute the given values.


4^2=5^2+7^2-2* 5 * 7 \cos P


16=25+49-70 \cos P


16=74-70 \cos P

Subtract 74 from both sides.


16-74=74-70 \cos P-74


-58=-70 \cos P

Multiply by -70 on both sides.


$ (-58)/(-70) =(-70 \cos P)/(-70)


$ (29)/(35) = \cos P


$\cos^(-1) (29)/(35) = P


$34^\circ = P

The measure of angle P is 34°.

User Miroslav Savovski
by
3.4k points