A) x + y = 17
B) x - y = 27
Adding both equations:2x = 44
x = 22
y = -5
9514 1404 393
Answer:
5x -y = -37
Step-by-step explanation:
One way to find the coefficients A and B is to use the differences of the x- and y-coordinates:
A = Δy = y2 -y1 = 2 -(-3) = 5
B = -Δx = -(x2 -x1) = -(-7 -(-8)) = -1
Then the constant C can be found using either point.
5x -y = 5(-7) -2 = -37
The equation of the line is ...
5x -y = -37
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<em>Additional comment</em>
This approach comes from the fact that the slope of a line is the same everywhere.
The "standard form" requires that A be positive, so we chose point 1 and point 2 to make sure that was the case.
Answer:
The x-intercept of CD is -19/5
Step-by-step explanation:
If the coordinates of the first point is (-3, 2) and the coordinates of the point B are (7, 6) then we need first to find the equation of the line CD:
We know that the general equation of the line is:
y-y0 = m(x-x0) where (x0, y0) represents a point that belongs to the line and m, is the slope which can be calculated by using the following formula:
m = (x1 - x0) / (y1 - y0)
In this case:
(x1, y1) = (7, 6)
(x0, y0) = (-3, 2)
Then:
m = (7 - (-3))/(6-2) = 10/4 = 5/2.
Then, the equation of the line is:
y-y0 = m(x-x0)
y - 2 = 5/2 (x -(-3))
y = 5/2(x+3) + 2
To find the x intercept we make y=0.
Then y = 5/2(x+3) + 2 = 0
Then:
x = -4/5 - 3 = -19/5
