SOLUTION: A line has a slope of 7. For each pair of points that are on the line (3,-6) and (7,y) , use the slope formula to find the missing coordinate. I know that y=22 but I do not know

Algebra ->  Graphs -> SOLUTION: A line has a slope of 7. For each pair of points that are on the line (3,-6) and (7,y) , use the slope formula to find the missing coordinate. I know that y=22 but I do not know      Log On


   

Question 178964: A line has a slope of 7. For each pair of points that are on the line (3,-6) and (7,y) , use the slope formula to find the missing coordinate.
I know that y=22 but I do not know how or the steps used to get the answer y=22
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Note: is the first point (3, -6) and is the second point (7, y)


m=%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29 Start with the slope formula

7=%28y-%28-6%29%29%2F%287-3%29 Plug in m=7 (the given slope) y%5B2%5D=y, y%5B1%5D=-6, x%5B2%5D=7, and x%5B1%5D=3 (the coordinates of the given points)


7=%28y%2B6%29%2F%287-3%29 Rewrite y-%28-6%29 as y%2B6


7=%28y%2B6%29%2F%284%29 Subtract


7%2A4=y%2B6 Multiply both sides by 4


28=y%2B6 Multiply


28-6=y Subtract 6 from both sides.


22=y Combine like terms.


So the answer is y=22