Question 444573: What is the slope - intercept for a line that passes through (-4,-3) and (-6,7)Show the work.
Answer by oberobic(2304)   (Show Source):
You can put this solution on YOUR website! Here we are given the two points that define a line: (-4,-3) and (-6,7).
We know the slope = change in y divided by the change in x.
That is often called "the rise over the run."
The change in x = -6 -(-4) = -2
The change in y = 7 -(-3) = 10
The slope = 10/-2 = -5
So we now have:
y = -5x + b
But what is b?
Well, looking back at what was given, we know that when x = -4, y = -3.
Plugging in x = -4
y = -5(-4) + b
y = 20 + b
So, b = -23 to arrive at the point (-4,-3)
We also have the point (-6,7)
Plugging these into the formula we have:
7 = -5(-6) + b
7 = 30 + b
b = -23
That's the same answer as before.
So, the answer is: y = -5x -23
The graph can be used to check this.
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