I see your last line is : c(x) = 0.9(x^2-10)^2 + 101.1
Let y = x^2, then c(y) = 0.9(y-10)^2 + 101.1
Apparently, c(y) is a parabola, min is 101.1 when y = 10, max is infinity
So let x^2 = 10 -> x = sqrt(10) or -sqrt(10), min is 101.1, max is infinity
        
                    
             
        
        
        
<span>Answer: 4*x+3=5+x
Explanation: four times a number means 4*x plus three means 4*x+3 is the same as which means = five plus the number which is 5+x </span>
        
             
        
        
        
Answer:
x=3
Step-by-step explanation:
First, combine like terms on the left side 
4x-5x+9=5x-9
-x+9=5x-9 
Subtract 9 on both sides 
-x=5x-18 
Subtract 5x on both sides 
-6x= -18 
Divide by -6 on both sides 
x=3 
Hope this helps! :)
 
        
                    
             
        
        
        
Answer:
103.95
Step-by-step explanation:
99×5/100=4.95
99+4.95=103.95