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Question 1000871: How do you graph a slope of -2/1 and a y intercept of -6,3?
Answer by Theo(13342)   (Show Source):
You can put this solution on YOUR website! you cannot have a y-intercept of (-6,3).
the y-intercept is the value of y when x = 0.
the x-coordinate of the point that contains the y-intercept must be equal to 0.
what you were given was a point and a slope as far as i can tell.
that point will be on the line but it is not the y-intercept.
the slope is -2/1 and the point is (-6,3).
you plot the point (-6,3) on your graph.
you pick any other value of x that's reasonably far enough away to that it's easy for you to draw a straight line between that new point and the original point.
i'll pick x = 0.
this will allow me to find the new point and the y-intercept at the same time.
the change in x is from -6 to 0 which is a change of 6.
to find the change in y, i multiply that change by -2/1.
this result in a change in y of -2*6 = -12.
the change in the value of x is 6.
the change in the value of y is -12.
from the point (-6,3), add 6 to the x-coordinate and subtract 12 from the y-coordinate to get (0,-9).
the point (0,-9) is the y-intercept.
it's the value of y when the value of x is 0.
draw a straight line between the points (-6,3) and (0,-9).
that's your graph.
the slope intercept form of the equation of a straight line is y = mx + b.
m is the slope and b is the y-intercept.
your equation is y = -2/1 * x - 9.
-2/1 is the slope.
-9 is the y-intercept.
the graph of y = -2/1 * x - 9 is shown below:
here's a good reference you can use to learn more about linear equations.
http://www.mathsisfun.com/algebra/linear-equations.html
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