Answer:
x= -1
Step-by-step explanation:
Solving through linear equation,
-0.1x + 3/10= 4/10
Bring 3/10 to the other side making it minus
-0.1x = 4/10 - 3/10
-0.1x = (4-3)/10
-0.1x= 1/10
Bring -0.1 to the other side n divide
x= 1/10 ÷ -0.1
( Note that -0.1 is the same as -1/10)
x = 1/10 ÷ -1/10
= 1/10*-10/1
= -10/10
= -1
 
        
             
        
        
        
Factors of 4 : 1,2,4
factors of 10 : 1,2,5,10
        
                    
             
        
        
        
Answer: -1t + 720
Step-by-step explanation:
He worked at both jobs for 90 hours for this month. 
He worked t hours as a tutor which means that as a waiter he worked;
= 90 - t hours 
The amount earned is therefore;
= 7t + (8 * (90 - t)) 
= 7t + 720 - 8t
= -1t + 720
 
        
             
        
        
        
A used book store buys a hardback book for $1.50 and then sells it for $5. Over time, the store sells the same number of books it buys. The store manager can use the equation P(x)=5x−1.5x to determine the store's profit, P(x), where x is the number of books that the store sells. Which statement about the book store is true based on the profit equation?
Cost Price of book, C.P.=$1.50
Selling Price of book, S.P.=$5
PROFIT=S.P. -C.P.
So, Profit=$5-$1.50=$3.50
So, Profit=$3.50 on each book
Or, we are given P(x)= 5x-1.50x
Or, P(x)=3.50x
For each book, we must divide the profit P(x) by x, that is, number of books
 
 
 
 
 
 
So, Profit for each book sold is $3.50
Answer:Option C