SOLUTION: A line with x-intercept -4 passes through (2,6) and (p,10). Find p.

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Question 35653: A line with x-intercept -4 passes through (2,6) and (p,10). Find p.
Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
If the x-intercept is -4, then it passes through (-4,0) as well as (2,6). So find the slope of the line through these two points. Remember that slope is
m=+%28Rise%29%2F%28Run%29+=+%286-0%29%2F%282-%28-4%29%29=6%2F6=1

Now find the slope from (2,6) to (p,10)
m+=+%2810-6%29%2F%28p-2%29=+4%2F%28p-2%29, which also must equal to 1 from the other slope you found.

4%2F%28p-2%29+=+1

Multiply both sides by (p-2):
%28p-2%29%2A%284%2F%28p-2%29%29+=+%28p-2%29%2A1
4+=+p-2

Add +2 to each side:
p=6

R^2 at SCC