Answer:
The surface area is equal to 
Step-by-step explanation:
The surface area of the triangular pyramid is equal to the area of its four triangular faces
so
In this problem
![SA=4[\frac{1}{2}(b)(h)]](https://tex.z-dn.net/?f=SA%3D4%5B%5Cfrac%7B1%7D%7B2%7D%28b%29%28h%29%5D)
we have


substitute the values
![SA=4[\frac{1}{2}(15)(13)]=390\ in^{2}](https://tex.z-dn.net/?f=SA%3D4%5B%5Cfrac%7B1%7D%7B2%7D%2815%29%2813%29%5D%3D390%5C%20in%5E%7B2%7D)
<h3>
Answer: 5</h3>
Explanation:
This is something you could do by trial and error.
The visible numbers are 1,2,3,4,6 which multiply to 144.
Another approach is to notice that 5 is not a factor of 144, so it must be the hidden value not part of the items multiplied.
Every other number 1,2,3,4,6 is a factor of 144.
1*144 = 144
2*72 = 144
3*48 = 144
4*36 = 144
6*24 = 144
A ratio is the quantitative relation between two amounts showing the number of times one value contains or is contained within the other.
Please mark as brainliest if this helped
Answer: The acute angle between diagonals is 50
Step-by-step explanation:
Red angle = 50 because An exterior angle of a triangle is equal to the sum of the opposite interior angles (pink angles).
Alternatively:
Green angle is 130 by sum of interior angles of a triangle.
Red angle is 50 by Adjacent angles