Answer:
Like terms are terms whose variables are the same.
We can only add them because if they does not have the same variable you do not actually know if the variables are equivalent and you will get the wrong answer.
Step-by-step explanation:
Ex: 4z,7z,108z,45z
Ex: 4w-2h+7a-2w
You can not add 4w and 7a because you do not know what the variables equal so you do not know the true number so add or subtract by.
 
        
             
        
        
        
Answer:
The radius of circle B is 6 times greater than the radius of circle A
The area of circle B is 36 times greater than the area of circle A
Step-by-step explanation:
we have
<em>Circle A</em>

The radius of circle A is
 -----> the radius is half the diameter
 -----> the radius is half the diameter
<em>Circle B</em>

Compare the radius of both circles


The radius of circle B is six times greater than the radius of circle A
Remember that , if two figures are similar, then the ratio of its areas is equal to the scale factor squared
All circles are similar
In this problem the scale factor is 6
so

therefore
The area of circle B is 36 times greater than the area of circle A
 
        
             
        
        
        
Answer:
880
Step-by-step explanation:
20 x 10% = 2
20 + 2 = 22
22 x 40 = 880
 
        
             
        
        
        
Answer:
<h3>Add to eliminate y.</h3>
Step-by-step explanation:
Given the equations
-9x + y =  71.... 1
-x - y = -1 .... 2
Using elimination method we can eliminate y first since they have the same coefficient.
To do that we will need to add up both equations. We are adding because the coefficient of y in both equations has different signs. If they have the same sign, we would have subtracted.
<em>Hence the correct option in this case is to add to eliminate y.</em>
 
        
             
        
        
        
Answer:
Domain: [3, ∞)
Range: [-1, ∞)
Step-by-step explanation:
lmk if you want an explanation