20 5/81 in its simplest form is 20 5/81.
20 5/81 originally looks like this ⇒ 1625/81
((20 * 81)+5)/81 = (1620+5)/81 = 1625/81   * this is an improper fraction because the numerator is greater than the denominator. Improper fractions must be converted to proper fractions. It will then become a mixed fraction.
 
     <u>  0020  5/81</u>        
81 | 1625
       <u>162      </u>      * 81 x 2
           05
        
             
        
        
        
F(x) = x^2 +5x + 3
     = (x + 2.5)^2 - 6.25 + 3
     = (x + 2.5)^2 - 3.25
That is vertex form. I am not sure what you mean by function form
        
             
        
        
        
Answer:
80
Step-by-step explanation:
The trick is to pick something that should be very easy to get an answer to. If you use a calculator, you are not estimating.  80 divide by 4 is like 8 divide by 4 which gives you 2. Then just add a zero. Here's another one you can try. Put your calculator away to do it. 12 chicken noodle  soup cans cost 14 dollars. About how much does 1 can cost
no cheating. No calculator. Is the cost of 1 can more or less than a dollar? If you said more, you've estimated correctly. 
Try it the other way. Suppose one can of the soup costs 0.95 cents. How many will 12 cans cost? More or less than 12 dollars.
If you said less, you are estimating correctly. The most useful gift you can take away from any math class is estimation. 
 
        
             
        
        
        
Answer:
h = hamburgers sold
2h - 72 = 578
2h = 650
 2       2
h = 325
There were 72 fewer cheeseburgers sold than hamburgers. That means cheeseburgers = 325 - 72
325 - 72 =  253
253 = cheeseburgers
325 = hamburgers
253 + 325 = 578
Hamburgers = 325
Hope this helps :)
 
        
             
        
        
        
An expression is a mathematical phrase containing at least one variable :)