SOLUTION: Find the slope intercept form of line that passes through a(1,5) and b(-4,-5)

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Question 729021: Find the slope intercept form of line that passes through a(1,5) and b(-4,-5)
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


Note: is the first point . So this means that x%5B1%5D=1 and y%5B1%5D=5.
Also, is the second point . So this means that x%5B2%5D=-4 and y%5B2%5D=-5.


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


m=%28-5-5%29%2F%28-4-1%29 Plug in y%5B2%5D=-5, y%5B1%5D=5, x%5B2%5D=-4, and x%5B1%5D=1


m=%28-10%29%2F%28-4-1%29 Subtract 5 from -5 to get -10


m=%28-10%29%2F%28-5%29 Subtract 1 from -4 to get -5


m=2 Reduce


So the slope of the line that goes through the points and is m=2


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-5=2%28x-1%29 Plug in m=2, x%5B1%5D=1, and y%5B1%5D=5


y-5=2x%2B2%28-1%29 Distribute


y-5=2x-2 Multiply


y=2x-2%2B5 Add 5 to both sides.


y=2x%2B3 Combine like terms.


So the equation that goes through the points and is y=2x%2B3


Notice how the graph of y=2x%2B3 goes through the points and . So this visually verifies our answer.
Graph of y=2x%2B3 through the points and