Question 156924: write a linear equation in standard form, given the following information...
A line through -3,2 and parallel to a line with a slope of -4
Found 2 solutions by checkley77, gonzo:
Answer by checkley77(12844)   (Show Source):
You can put this solution on YOUR website! 2=-4*-3+b
2=12+b
b=2-12
b=-10
Thus the line equation is:
Y=-4X-10
 (graph 300x200 pixels, x from -6 to 5, y from -10 to 10, -4x -10).
Answer by gonzo(654) (Show Source):
You can put this solution on YOUR website! i believe this meets your requirements.
check it out and let me know what you think.
i used the slope intercept formula to get the equation.
the formula is: y = mx + b where m is the slope and b is the y-intercept.
i started with  since -4 is the slope of the line you wanted this line to be parallel to.
getting the y intercept was a little tricky but here's how i did it.
i plotted for x points from -5 to + 5.
i then started with x = -3 to fix the line to pass through where you wanted it to. i set the y value at 2 at that point (line goes through (-3,2).
with a slope of -4 there is a drop of 4 units in the y value for every increase of 1 unit in the x value. conversely there is an increase of 4 units in the y value for every decrease of 1 unit in the x value.
the plot poiints look like the following:
start of plot points........
x,y
-5,10
-4,6
-3,2
-2,-2
-1,-6
0,-10
1,-14
2,-18
3,-22
4,-26
5,-20
end of plot points.............
looking at this table i saw that the y-intercept (y value when x is 0) is -10.
the equation then becomes 
the graph looks like the following:
an algebraic way to find the b value in the equation would be as follows:
starting with , i would solve the equation for  .
 yields  .
the answer i want is 2 so i would need to subtract 10 from it.
that becomes my b value, so the equation then becomes  which is the same result without looking at plot points.
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