SOLUTION: Find an equation of the line through(-1, 2) and (3, 10)

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Question 973432: Find an equation of the line through(-1, 2) and (3, 10)
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
First find the slope, which is the difference between the xs and the ys going in the same direction.
(10-2)= difference in y, or 8
3-(-1)=4, difference in x
slope is y/x, and that is (8/4)=2
Now use point slope formula
y-y1=m (x-x1)
m is slope, and you may use either point. You will get the same answer.
y-10=2(x-3)
distribute
y-10=2x-6
add 10 to both sides
y=2x+4
Alternative is use y=mx+b where y is 10, m=2, x=3
10=2(3)+b
10=6+b
b=4
y=2x+4
graph%28300%2C300%2C-10%2C10%2C-10%2C12%2C2x%2B4%29