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according to the code of Mathematical Logic, there exists more properties, one of its principles is the consequence and effects property, or the so-called equivalence implicationwhich is defined as follows:Two expressions A and B are equivalent if A can produce B, and B can produce A. It means A implies B and B implies A.</span>
Answer:

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Step-by-step explanation:


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Answer:
M= -7
Step-by-step explanation:
M+9=2
M =2-9
M=-7
Get the y by itself
-2y= -3x + 1
Divide -2 to everything
y= 3/2x - 1/2
Other equation (get y by itself)
-6y= -9x + 3
y=3/2x - 1/2
Use substitution
3/2x-1/2=3/2-1/2
0=0
All real numbers (any value of x makes the equation true)
Answer:
A= 115 degrees
C= 50 degrees
Step-by-step explanation:
All angles are equal to 180 so the equation is:
180=4x-13+x+18+15
180=5x+20
160=5x
x=32