Question 1:
 The generic equation of the line is given by: 

 Where,
 m: slope of the line
 b: cutting point with the y axis
 Substituting values we have: 
 Answer: an equation for the line with slope 2/3 and y-intercept is:
 Answer: an equation for the line with slope 2/3 and y-intercept is:  Question 2:
 Question 2:
 The standard equation of the line is given by: 

 Where,
 m: slope of the line
 (xo, yo): ordered pair that belongs to the line
 The slope of the line is: 

 Substituting values: 
 
  
  
 
 We choose an ordered pair: 

 Substituting values: 

 Rewriting: 
 Answer: An equation in slope-intercept form for the line that passes through the points (1, -3) and (3,1) is:
 Answer: An equation in slope-intercept form for the line that passes through the points (1, -3) and (3,1) is:  Question 3:
 Question 3:
 For this case, since the variation is direct, then we have an equation of the form: 

 Where,
 k: constant of variation.
 We then have the following equation: 

 Rewriting we have: 
 
 
 Therefore, the constate of variation is given by: 
 Answer: the constant of variation is:
 Answer: the constant of variation is:  Question 4:
 Question 4: For this case, since the variation is direct, then we have an equation of the form: 

 Where,
 k: constant of variation.
 We must find the constant k, for this we use the following data:
 y = 24 when x = 8
 Substituting values: 

 Clearing k we have: 
 
 
 Therefore, the equation is: 

 Thus, substituting x = 10 we have that the value of y is given by: 
 Answer: the value of y when x = 10 is:
 Answer: the value of y when x = 10 is:
 