The equation is

If you put in the numbers you get

This comes to 1056. So the answer is 1056 in^2
Congruent means they are the same size
To prove the two triangles are congruent you would need to know the length of at least two of the sides. If two sides were not known you would need to know the length of one side and at least one of the unknown angles.
Answer:
Square shaped = 27 cubic inches , Rectangular shaped = 3LW cubic Inches
Step-by-step explanation:
If the dictionary is a square ( all sides are equal ) the the volume is
V = Length * Length * Length = 
V = 3 * 3 * 3 = 27 
while if its rectangular ( all side are not equal ) shaped
V = Length * Width * Height (thickness)
V = L * W * 3 = 3LW 
Answer:
Felipe = 23 messages
Keisha = 31 messages
Manuel = 46 messages
Step-by-step explanation:
Keisha = K
Felipe = F
Manuel = M
=> There are a total of 100 messages.
=> K sent 8 +F => K = 8 + F
=> M sent 2 * F => M = 2F
=> F = F
=> 8 + F + 2F + F = 100
=> 8 + 4F = 100
=> 8 - 8 +4F = 100 -8
=> 4F = 92
=> 4F/4 = 92/4
=> F = 23
So, Felipe = 23 messages.
Keisha = 8 + F = 8 + 23 = 31 messages.
Manuel = 2F = 2* 23 = 46 messages.
46 + 31 + 23 = 77 + 23 = 100 messages.
So, the answer is correct.