Answer:
answer is 90 for first term 
Step-by-step explanation:
Let the terms be  
First term x
We will use the formula s∞=x/1−r to find the sum of an infinite geometric series, where −1<r<1.  
We know the sum and the common ratio, so we'll be solving for x where r =4/5
s∞=x/1−r
450=x/1−4/5
450=x/1/5
450=5x
x=90
this is the first term x1 = 90
we know that common ratio is 4/5, so multiplying the first term by factor 4/5 to get the second term  
 90 x 4/5=   72 second term  
 
        
                    
             
        
        
        
You can't. If you think about the straight line on a graph, those numbers 
describe a single point that the line goes through, and they don't tell you 
anything about the slope of the line, or where it crosses the x-axis or the 
y-axis.  So I don't think you can tell the constant of variation from one point.
        
                    
             
        
        
        
Answer:
AC=18
Step-by-step explanation:
To find AC, use the Pythagorean Theorem.  Since the longest side (hypotenuse) is known, instead of a²+b²=c², the equation will be c²-a²=b².  12²-8²=b²
144-64=b²
80=b²
√80=√b²
8.94427191=b
That is for one of the two right triangles that make up the tent.  Since there are 2 triangles, 8.94427191 only equals BC or AB.  So, multiply 8.94427191×2=17.88854382 to find the length of AC.
AC= 18
 
        
             
        
        
        
The answer is ....1.237149 x 10^18