Aline passes through (9, –9) and (10, –5).write an equation for the line in point-slope form. rewrite the equation in standard form using integers. y 9 = (x – 9); –4x y = –45 y 9 = (x 9); –4x y = –45 y – 9 = (x 9); –4x y = 45 y – 9 = (x – 9); –4x y = 45

The equation of the line in point-slope form is given by:
 
 Where,
 (xo, yo): point that belongs to the line
 m: slope of the line
 The slope is given by:
 
 Substituting values:
 
 Rewriting:
 
 
 
 Now we choose an ordered pair:
 
 Substituting values we have:
 
 
 We now rewrite the equation in its standard form:
 
 Where,
 b: cut with the y axis.
 We have then:
 
 
 point-slope form:
 
 or
 
 standard form