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Question 273601: How do I properly graph this equation on algebra.com? x-4y=-8
I know that rise=2 run=8 and slope=1/4
My original task was to find the rise, run, and slope and then write in standard form after looking at a graph. that had a line on it.
I understand that Ax+By=C
I don't quite understand what Ax is, Bx, or C. The original problem didn't have the standard form answer of x-4y=-8, that was in the back of my text book.
I have included what I thought was the correct graph, but all it did was draw a horizontal line.
So, if you can show me what I am missing in the computer formula I would appreciate it. I would love for someone to explain how to get the standard form out of the given information
graph( 300, 200, -6, 5, -10, 10, x-4y=-8)
Answer by Theo(13342)   (Show Source):
You can put this solution on YOUR website! standard for of the equation for a line is Ax + By = C
A is the coefficient of the x variable.
B is the coefficient of the y variable.
C is the constant.
your equation is:
x - 4y = -8
in your equation, which is in standard form, ....
A = 1
B = -4
C = -8
to graph this equation, you need to solve for y.
at the same time you will be putting this equation into the slope-intercept form of it.
subtract x from both sides of this equation to get -4y = -x - 8
divide both sides of this equation by -4 to get y = (1/4)*x + 2
the slope intercept form of the equation for a line is y = mx + b where m is the slope and b is the y intercept.
in your equation, the slope is (1/4) and the y intercept is 2.
when you graph in algebra.com, you have to solve for y as we just did.
you then enter ONLY the right side of the equation. you do not enter the y.
to graph your equation you would put the following between the starting 3 brackets and the ending 3 brackets.
graph (600,600,-10,10,-10,10,(1/4)*x + 2)
the first 600 is the width of the graph.
the second 600 is the height of the graph.
the first -10 is the low end of the x-axis.
the first 10 is the high end of the x-axis.
the second -10 is the low end of the y-axis.
the second 10 is the high end of the y-axis.
the right side of your equations after you have solved for y goes next.
here's what the graph of your equation looks like.
I just took that expression and enclosed it in the brackets.
assuming you were given the equation in slope intercept form to start with, then you were given:
y = (1/4)x + 2
to convert this to standard form, you want to get the x and y on the left side of the equation and the constant term on the right side of the equation.
you would multiply both sides of the equation by 4 to get:
4y = x + 8
you would then subtract x from both sides of the equation to get:
-x + 4y = 8
that's the standard form of the equation where A = -1 and B = 4 and C = 8
if you multiply both sides of this equation by -1 you would get:
x - 4y = -8
that's the standard form of the equation where A = 1 and B = -4 and C = -8
the two equations:
-x + 4y = 8
x - 4y = -8
are equivalent.
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