The slope of y=2x+1 is: 2. The parallel line needs to have the same slope of 2. We can solve it using the point-slope equation of a line: y â y1 = 2(x â x1) And then put in the point (5,4): y â 4 = 2(x â 5) And that answer is OK, but let's also put it in y = mx + b form: y â 4 = 2x â 10.
1 In-office teeth whitening treatments by a dentist can cost $300-$1,000 or more, but average about $500-$700.
1 The results typically last up to a year or longer.  For in-office treatments, a whitening product is applied directly to the teeth. Often heat, light or a laser is used to accelerate the process. Treatments last 30 to 60 minutes.