Answer:
The solution for this system is: 
Step-by-step explanation:
The problem states that we have to solve this system by the elimination method
In the elimination method, we transform the system in such a way that one variable can cancel each other. With this, we find the result of the other variable. Then, we can replace the variable we found in any of the equations, and we have the value of the variable that we had initially canceled.
In this problem, we have the following system:


If we add equations 1) and 2), the variable x is going to be eliminated





Now, we can replace the value of y in any of the equations, to find x:
I will replace in equation 2)





The solution for this system is: 
The answer to the problem is D
Answer:
slope is 3/4
Step-by-step explanation:
the slope is just what is attached to the x
#3 is a triangular pyramid because triangular pyramids have 4 triangular faces.
#4 is a cube because there are 6 square faces.
#5 is a triangular prism. It has 2 triangular faces and 3 rectangular faces.
#6 is a rectangular prism. It has 2 square faces and 4 rectangular faces.
(If you don't know what the figure of the net is, resketch it on another piece of paper, cut it out, and form it.)
Hope this helps,
Loafly
Answer:
D. 100
Step-by-step explanation:
Mean = Sum of all numbers divided by the count of all numbers
Mean = 50
Let say that the sum of all numbers = X
50 = X / 4
200 = X
X = (20+30+50) + The 4th Value
200 = 100 + 4th Value
The 4th Value = 100