Answer: B 
Step-by-step explanation:
7(-2) - 4(1) = -18 
-14 - 4 = -18 
-18 = -18 
TRUE 
(-2) + 12(1) = 10 
-2 + 12 = 10
10 = 10 
TRUE
 
        
             
        
        
        
Answer:
The equation of any straight line, called a linear equation, can be written as:   y = mx + b, where m is the slope of the line and b is the y-intercept.               The y-intercept of this line is the value of y at the point where the line crosses the y axis.
 so to find that you can use y=mx+b, or you can use point slope form and that would be y-y1+m(x-x1) 
remember m= slope b= y- intercept
 
        
             
        
        
        
5300 and 6000 is the elevation in miles
        
             
        
        
        
Realistically would be 20.