Answer:
likely .
Step-by-step explanation:
 
        
                    
             
        
        
        
Answer:
c. 4x + 20 = 140
Step-by-step explanation:
Perimeter = 140 feet
Width = L + 10
P = 2w + 2L
P = 2(L + 10) + 2L
P = 2L + 20 + 2L
P = 4L + 20
 
        
             
        
        
        
Answer:
There are 75 pencils and 25 pens.
Step-by-step explanation:
If Tom has three times as many pencils than pens then,
Pencils = 3(Pens)
If there are a total of 100 writing utensils then,
Pencils + Pens = 100
Substitute the word "pencils" in this equation to 3(Pens),
3(Pens) + Pens = 100
Now remember there is almost a 'hidden' one beside the word "Pens" so,
3Pens + 1Pens = 100
Add the two together,
4Pens = 100
Divide,
Pens = 25
Substitute 25 into the first equation,
Pencils = 3(25)
Pencils = 75
Thus, there are 75 pencils and 25 pens.
 
        
             
        
        
        
Answer:
- 3
Step-by-step explanation:

 
        
             
        
        
        
If you multiply the top equation by -2 you get:
-4x -14y = 14 => -4x = 14+14y
now you can plug in the -4x into the second equation:
 14+14y - 3y = -19 => 11y = -33 => y=-3
Fill in y=-3 in either equation to find x:
2x - 21 = -7 => 2x = 14 => x=7
So your ordered pair is (7,-3)