Answer:

Step-by-step explanation:
we know that
The formula of law of cosines is equal to

where
a, b and c are sides. C is the angle opposite side c
In this problem we have

 
 
substitute the given values






 
        
             
        
        
        
Answer: 
Step-by-step explanation: Ok so it is backwerd to pas would be nagitv
 
        
             
        
        
        
Answer:
B and D
Step-by-step explanation:
This must be a six sided figure
 A. 15 x 15.  This would be area
B. 6 x 15.   This is the sum of six sides of 15
C. 15 + 6.  This is the sum of 2 sides of different length
 D. 15 + 15 + 15 + 15 + 15 + 15.  This is the sum of six sides of length 15
 
        
                    
             
        
        
        
The intersection of altitudes traced perpendicularly from a triangle's vertices to its opposite sides is known as an orthocenter.
Given that,
We have to find what is orthocenter.
We know that
<h3>What is Orthocenter?</h3>
The intersection of altitudes traced perpendicularly from a triangle's vertices to its opposite sides is known as an orthocenter. It is the location in a triangle where the three angles of the triangle intersect. An orthocenter's three primary characteristics are as follows:
Triangle: A three-sided polygon with three edges.
A triangle's height is the line that runs between its vertices and perpendicular to the other side. A triangle can therefore have three heights, one from each vertices.
Vertex - A vertex is the intersection of two or more lines.
To learn more about orthocenter visit: brainly.com/question/19763099
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