Step-by-step explanation: x= 2-y then plug that in for x so y= 2-y+2;
y=4-y; -4y=-y; y=-1/4
A plastic skeleton is
Answer: B. a physical model.
The world has lots of different kinds of models. A mathematical model might be a ball travels according to the equation 
. This isn't that. A computer model would be a program that somehow simulates a skeleton in the computer, this isn't that either. Our skeleton is an actual physical model just like a model airplane.
Answer:
M
Step-by-step explanation:
5 comes from point M
I hope this is good enough for you:
2(x-3)=7x-31
2x-6=7x-31
-7x -7x
----------------
-5x-6=-31
+6 +6
--------------
-5x=-25
Divide by -5
x=5
3x-2(x+5)=-3+18
15
3x-2(x+5)=15
3x-2x-10=15
x-10=15
+10 +10
--------------
x=25
