Answer:
For the top equation, x = 27 (I think you meant to put x - 27 = 0. If not, I can always edit my answer for you)
For the bottom, x = 3
Hope this helps! Have a grrrreat day lol
 
        
             
        
        
        
9514 1404 393
Answer:
   B.  (x +4)² +(y +5)² = 64
Step-by-step explanation:
The equation for a circle with center (h, k) and radius r is ...
   (x -h)² +(y -k)² = r²
Filling in your given values, you have ...
   (x -(-4))² +(y -(-5))² = 8²
Simplifying, you get ...
   (x +4)² +(y +5)² = 64 . . . . . . . matches choice B
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<em>Additional comment</em>
As you learn more different "standard form" equations, it may be helpful to keep a list, along with reminders of what the variables stand for and how the equation is used.
 
        
             
        
        
        
A pyramid is regular if its base is a regular polygon, that is a polygon with equal sides and angle measures. 
(and the lateral edges of the pyramid are also equal to each other)
Thus a regular rectangular pyramid is a regular pyramid with a square base, of side length say 
x.
The lateral faces are equilateral triangles of side length 
x.
The lateral surface area is 72 cm^2, thus the area of one face is 72/4=36/2=18  cm^2.
now we need to find 
x. Consider the picture attached, showing one lateral face of the pyramid.
by the Pythagorean theorem: 

thus, 

thus:

       (cm^2)
but 

 is exactly the base area, since the base is a square of sidelength = 
x cm.
So, the total surface area = base area + lateral area =  

   cm^2
Answer: 

   cm^2
 
        
        
        
Answer:
x = 5/3
Step-by-step explanation:
You ALWAYS want your term to be by itself!! So what you need to do is move your constant away from it.
Step 1:  Adjust as needed, subtract 10 from both sides of your equation. It should end up like this.
-3x = 5 - 10
Step 2: Solve as needed before continuing equation.
-3x = -5
Step 3: Now you need to get your term by itself. You should divide -3 on both sides of your equation so you should get something like this.
x = -5 / -3
Step 4: You're basically done now! Just simplify! NEGATIVES CROSS EACH OTHER OUT!!!
x = 5/3 OR 1.6
<em>KEY:</em>
<em>Negative and Negative = Positive</em>
<em>Negative and Positive = Negative</em>
<em>Positive and Positive = Positive</em>