Answer:
i think... x=6
Step-by-step explanation:
3x+9=x+21
3x−x=12
2x=12
x=6
 
        
             
        
        
        
Answer:
C: 2m + 1
Step-by-step explanation:
If m + 1 is even, then m is odd.
A: m - 1 is even
B: 2m - 2 is even
C: 2m + 1 is odd
D: 2m + 2 is even
 
        
                    
             
        
        
        
Answer: $70 per year. 
Step-by-step explanation:
Let's say that x is the number of years that has passed and y is how much the stamp is worth. 
So we know that in zero years the stamp was worth $420 because that is the time Sheri gave her brother Sam the stamp. That could bring up the coordinates  (0,420) . 
Now we know that in 8 years it was worth $980 and that could be the coordinates (8,980) 
To find the rate of change we need to find the different between the y value and divide it by the difference in the x values. 
420 - 980 = -560 
  0-8 = -8 
-560/-8 = 70 
The rate of change is 70 which means that it grew by $70 every year. 
 
        
             
        
        
        
Answer:
the original price would be <u>16.605.</u>
Step-by-step explanation:
 
        
             
        
        
        
Answer: 3 1/3 liter
Brainliest? <3
let x equal the number of liters of 15% weedkiller.
your equation is .15 * x + .10 * 5 = .12 * (x + 5)
simplify to get .15 * x + .10 * 5 = .12 * x + .12 * 5
simplify further to get .15 * x + .5 = .12 * x + .6
subtract .12 * x from both sides and subtract .5 from both sides and simplify to get .03 * x = .1
divide both sides by .03 to get x = .1 / .03 = 3.333333333 rounded to 9 decimal digits.
you would need 3.333333333 liters of 15% solution to be added to 5 liters of 10% solution to get 8.333333333 liters of 12% solution.
.15 * 3.333333333 = .5
.10 * 5 = .5
.5 + .5 = 1
5 + 3.333333333 = 8.333333333
1 divided by 8.333333333 = .12 which is equal to 12%.