Asker Potrait
hamood0-0-blog asked

Hello I want to ask how can I solve kind of questions like this " What is the y-Intercept of the lines that passes through the points (1,1) (5,13) " ???

My preferred method is to calculate the slope:

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From there, all you need to do is use the slope to count back to the y-axis from the closest point you have. In this case, you start at (1, 1), then count down 3, left 1 and you’re at (0, –2). The y-intercept is –2. 

The other way to go is to memorize the point-slope form. (This would be the preferred method if you think you’re not going to land on a nice, neat number.)

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There, the slope is m and either of the points is (x_1, y_1). So we can plug in the y-intercept.

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Notes
  1. hamood0-0-blog said: Thanks ^_^
  2. pwnthesat posted this