Example 1 - no calculation required
The slope and the y-coordinate of the y-intercept are given (a point with x = 0 is the y-intercept). Match them to the answer choices given as y = mx + b equation.
Example 3 - no calculation required
The slope can be determined from the graph as rise/run. The y-intercept can be directly read from the graph. Match them to the answer choices given as y = mx + b form equation.
Example 6 - mental math
From the equation, the slope can be read as rise/run = shift in y/shift in x. Staring with the given point, add rise to y and run to x. Hence, (2 + rise),(2 + run) is the next point. Continue this till the correct answer is reached.