Answer:
Think of y = mx + b,
With y = x + 3, m = 1 so the slope is one, and b = 3 which is the y-intercept, so plot the point (0,3) on the y-axis.
To find the next point to plot go up 1 and over to the right 1 because slope is rise over run.
With y = x, the slope is still 1, but there is no y-intercept, so you plot the point (0,0), and to find the next point on that line, go up 1 and over the right 1 because m=1
 
        
             
        
        
        
Y=15+5g
Y is the total cost in one month. 15 is the cost of the membership and 5 is the amount you paid to see the game. G is the variable for the amount of games. You multiple the g by 5 to get the total cost of games per a month that you went and saw. Than you add the base cost of 15 or your starting point. And you get your total cost.
        
                    
             
        
        
        
Answer:
Key features: the functions can not be parallels, this means that their respective slopes can not be equal or multiple to the other
Step-by-step explanation:
Take for instance 2 linear functions,  and 
If they intersect in some point in the space, say that is 
Then (x1,y1)=(x3,y3), (x2.y2)= (x3,y3)
So, we can compare the two functions and get the following result;
It tells us that if M=m, we get an error, meaning that the functions are in fact parallels and there is no way that they meet in some point.
hope this helps!