Combine like terms 
2m and -4m are like terms while 3m^2 isnt. So, leave 3m^2 as it is and combine the other set. 2m-4m = (-2m). Therefore, your answer should be 3m^2 - 2m
        
             
        
        
        
The way to calculate the perimeter for this particular shape would be 3x15 being as there is three 15 inch sides and when we do the multiplication we get 45 so the perimeter is 45inches have a nice day and please mark brainliest
        
             
        
        
        
Step-by-step explanation:
The question needs to be more specific. But assuming it is 0.5y/(4/9), I will solve it.
This would make it 4.5y/4 =y + 3/8
- Multiply 4 to both sides
4.5y = 4y + 12/8
- Subtract 4y to both sides
0.5y = 12/8
- Divide both sides by 0.5
y = 3
Now plug in to check.
0.5(3)/(4/9)=3+3/8
Both equals 3.375!
If this helped, please feel free to pick this answer as the brainliest! Thank you very much and have a wonderful day!
 
        
             
        
        
        
(13 + x)/(50 - x ) = (2/1)
Cross Multiply
2(50-x) = 1(13 + x)
100 - 2x = 13 + x
add 2x to both sides
100 -2x + 2x = 13 + x + 2x
100 = 13 + 3x
Subtract 13 from both sides
100 - 13 = 13 - 13 + 3x
87 = 3x 
divide both sides by 3
29 = x
(13 + 29)/(50-29) = 42/21 = 2 to 1 ratio