Q:

Find the equation of the line passing through the coordinates ( 1 , 8) and ( 3, 18).

Accepted Solution

A:
Answer:y = 5x + 3Step-by-step explanation:First we need to find the slope.The equation to find the slope is m = y2 - y1/x2 - x1  -----> (x1 and x2 just mean the x coordinate for the 2 points, so basically in this case, x1 would be 1 and x2 would be 3. Same for y1 and y2, just the y coordination of each point. y1 = 8 and y2 = 18)m = 18 - 8/ 3 - 1m = 10/2m = 5The slope would be 2 or 2/1. If you have a fraction that does not divide evenly, such as 3/5, DO NOT simplify unless specified. Now that we have the slope, we can put this into point-slope form. The formula for this form is:y - y1 = m(x - x1)For this you would have to choose one of your points.I'm going to choose the first one.y - 8 = 5(x - 1) ----> Always remember in this formula the "m" is the slope, and we previously found out that it was 2, so plug 2 into mFrom here just do basic multiplication and addition/subtraction.y - 8 = 5x - 5   +8          +8y = 5x + 3To test to see if these go through your points, plug the 2 points and equation into a website called desmos. (Very good site, and if your teacher has not recommend it, I highly advise using it. )