Step-by-step explanation:
2a - 7 - 6a = 9
- 4a - 7 = 9
- 4a = 16
a = -4
Answer:

Step-by-step explanation:
I assume that the three points given are the vertices of the triangle. So the three points are:
A (-4,1)
B (-7,5)
C (0,1)
The area of a triangle is given by:

where b is the base and h is the height.
Here we can take as follows:
- We can take the base to be the side AC, so that its length is equal to the distance between the two points:

- The height of the triangle is therefore the perpendicular distance between AC and point B. This is equivalent the difference in the x-coordinate between any point on AC and B, so:

Therefore, the area of the triangle is:

<span>The distance from the vertex to the centroid is twice the distance from the centroid to the side.
This means that 3x + 5 = 2 * (2x)
</span><span>3x + 5 = 4x
x = 5
Source:
http://www.1728.org/trictr.htm
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<span>1) Write the point-slope form of the equation of the horizontal line that passes through the point (2, 1). y = 1/2x
2)Write the point-slope form of the equation of the line that passes through the points (6, -9) and (7, 1).
m = (-9 - 1) / (6 - 7) = -10/-1 = 10
y + 9 = 10 (x - 6)
y = 10x - 69
3) A line passes through the point (-6, 6) and (-6, 2). In two or more complete sentences, explain why it is not possible to write the equation of the given line in the traditional version of the point-slope form of a line.
4)Write the point-slope form of the equation of the line that passes through the points (-3, 5) and (-1, 4).
m = (5 - 4) / (-3 - -1) = 1/-2
y - 5 = (-1/2) (x +3)
y = (-1/2)x + 7/2
5) Write the point-slope form of the equation of the line that passes through the points (6, 6) and (-6, 1).
m = (6-1)/(6 - -6) = 5 / 12
y - 6 = (5/12) (x-6)
y = (5/12)x + 17 / 2
6) Write the point-slope form of the equation of the line that passes through the points (-8, 2) and (1, -4).
m = (2 - -4) / (-8 -1) = 6 / -7
y - 2 = (-6/7) (x + 8)
y = (-6/7)x - 50 / 7
7) Write the point-slope form of the equation of the line that passes through the points (5, -9) and (-6, 1).
m = (-9 - 1) / (5 - -6) = -10 / 11
y + 9 = (-10 / 11) (x - 5)
y = (-10 / 11)x -49/11
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