Answer:
<h2>
11.11 square yard </h2>
Step-by-step explanation:
Step one:
given data
charges=$90
installation=$9 per square yard 
total cost of installation= $810
let x represents the number of square feet
Step two:
The expression for the installation cost is given as
810=9x+90------------1
solve for x, collect like terms
810-90=9x
720=9x
divide both sides by 9 we have
x=720/9
x=11.11 square yard 
 
        
             
        
        
        
Distance between -4 and -3 is 1 and there is no distance between 0
        
                    
             
        
        
        
Answer:
8.5 inches
Step-by-step explanation:
First let's find the time t when the depth of the snow is 7 inches.
To do this, we just need to use the value of D = 7 then find the value of t:



We want to find the depth of snow one hour from now, so we just need to use the value of t = 3 to calculate D:


The depth of snow one hour from now will be 8.5 inches.