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Question: can you please help me with this equation..
what is the slope and y-intercept for the line:-10x-5y+20=0
Answers:

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Solved by pluggable solver: DESCRIBE a linear EQUATION: slope, intercepts, etc

Equation describes a sloping line. For any equation ax+by+c = 0, slope is . X intercept is found by setting y to 0: ax+by=c becomes ax=c. that means that x = c/a. -20/-10 = 2. Y intercept is found by setting x to 0: the equation becomes by=c, and therefore y = c/b. Y intercept is -20/-5 = 4. Slope is --10/-5 = -2. Equation in slope-intercept form: y=-2*x+4.

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You can put this solution on YOUR website!
-10x-5y+20=0
Re-arrange the equation.
-5y = 10x-20
-5y/-5 = (10x/-5)-(20/-5)
y = -2x+4
J-Man

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Question: How do you find the line parallel to another line ex. x + 2y = 7
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A parallel line to a given line is one that has the same slope, but a different y-intercept.
The slope-intercept form of the equation of the line x+2y = 7 is y = -1/2 x + 7/2
So any line with the equation y = -1/2 x + b [b not equal 7/2] will be parallel.
Here's a graph of a couple of such lines with b= 3/2 and 6:

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Question: "Please help me solve this question" "What is the slope of x+y=4"
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You can find thr slope of a linear equation by putting the equation in the "slope-intercept" form: y = mx + b m is the slope, b is the y-intercept.
x + y = 4 Rewrite as: y = -x + 4 and compare with y = mx + b
m = -1, so the slope is -1.

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Question: How do you draw a line with a given slope? Ex, -3 as the slope
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You can draw a line knowing only the slope, you must also have another piece of information that gives you a starting point. For example, a line is a slope of -3 that crosses (0, 0) is different then the line with slope -3 that crosses (1, 1).


So let's assume our line crosses (0, 0). To draw this line, we have to understand something about the slope. A common description is the slope is the rise over the run, in other words a slope of 1/2 means you move up 1 space and to the right 2 spaces.


Well this is fine when the slope is a positive fraction, but what about a negative whole number? Well, there are two points to keep in mind. First, a whole number is a fraction, for example, the whole number 3 is the fraction 3/1. So, a slope of three means move up three spaces and to the right 1 space. The negative means you can either move down then to the right, or you can move up and to the left. The slope -3 means move down three spaces and one to the right or move up three spaces and one to the left.


So how does this help in drawing the graph. Well, if you start at (0, 0), you you can find a point by moving down 3 and one to the right this will land you at (1, -3), you can do this again to get to (2, -6) and so on. You can also, starting at (0, 0) move up three and to the left one, which brings you to (-1, 3).

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Question: Hello,
How do you find where a liine intercepts another point on a graph.
For example:
Line y=2/3x+13.5 and Line y=-1/2x+3
where do they intersect?
thank you
Answers:

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they intersect...think about it...this is where the 2 lines are equal. So at that point, their x-vlaues are the same and their y-values are the same.

So, we have y=2/3x+13.5 and y=-1/2x+3, so we can equate their y-values, as follows:

2/3x+13.5 = -1/2x+3 --> assuming it is just 1/2x and not 1/(2x+3)...you really show use brackets more, to avoid confusion!




--> moving the x to the righthand side and the -10.5 to the lefthand side gives

-7/63 = x

--> x = -1/9

jon.

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