Answer: 3/4 of an hour left. 
Step-by-step explanation:
Step 1:  2 hours = 4/4 +4/4
Step 2: 4/4 - 2/4 = 2/4 
Step 3: 4/4 - 3/4 = 1/4
Step 4: 2/4 + 1/4= 3/4 
 
        
             
        
        
        
The slope is the factor in front of x, so slope is 9.
The y intercept is 7 (that's the point of cross the y axis, where x=0)
There are multiple definitions of "standard form" for lines, so here are the two i can think of:
9x - y = -7    (the implicit function form)
or 
y-7 = 9*(x-0)  (the point-slope form)
Lmk if you have questions. 
 
        
             
        
        
        
The answer is x=5 and y=-2
 
        
        
        
Root: (-4/3, 0) 
vertical intercept: (0, -4)
 
        
        
        
Please provide us with more info, then we'll gladly answer