Answer:
being smart
Step-by-step explanation:
9514 1404 393
Answer:
288 km²
Step-by-step explanation:
The surface area is the sum of the area of the square base and the area of the four triangular faces.
SA = (10 km)² + 4(1/2)(10 km)(9.4 km) = 288 km²
____
The area formulas for a square and a triangle are ...
A = s² . . . . area of a square of edge length s
A = 1/2bh . . . . area of a triangle with base b and height h
![\left[\begin{array}{ccc}-1&2&1\\1&-4&1\\-2&-2&1\end{array}\right]](https://tex.z-dn.net/?f=%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-1%262%261%5C%5C1%26-4%261%5C%5C-2%26-2%261%5Cend%7Barray%7D%5Cright%5D%20%20)
Find the determinant
D = [(-1).(-4).1 + 2.1.(-2) + 1.1.(-2)] - [1.(-4).(-2) + (-1).1.(-2) + 2.1.1]
D = [4 - 4 - 2] - [8 + 2 + 2]
D = -10 - 12
D = -22
A = |D|/2
A = |-22|/2
A = 22/2
A = 11
Answer: 8X - 2 I believe
Explanation: If you add 3X + 5X you get 8X since you can’t add them with the whole numbers without a variable. After that you add 4 + -6 (4 - 6) either that or its 8X + 10