SOLUTION: I need to find a equation for this two points (42,20)and (52,10)

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Question 150342: I need to find a equation for this two points (42,20)and (52,10)
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

First let's find the slope of the line through the points and


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


m=%2810-20%29%2F%2852-42%29 Plug in y%5B2%5D=10, y%5B1%5D=20, x%5B2%5D=52, x%5B1%5D=42, ,


m=%28-10%29%2F%2852-42%29 Subtract 20 from 10 to get -10


m=%28-10%29%2F%2810%29 Subtract 42 from 52 to get 10


m=-1 Reduce


So the slope of the line that goes through the points and is m=-1


Now let's use the point slope formula:


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


y-20=-1%28x-42%29 Plug in m=-1, x%5B1%5D=42, and y%5B1%5D=20


y-20=-1x%2B-1%28-42%29 Distribute


y-20=-1x%2B42 Multiply


y=-1x%2B42%2B20 Add 20 to both sides.


y=-1x%2B62 Combine like terms.


y=-x%2B62 Simplify


So the equation that goes through the points and is y=-x%2B62