First, we'll determine the equation of the line that
passing through the given points (4,4) and (20,12).
(20 -
4)/(x - 4) = (12 - 4)/(y - 4)
16/(x - 4) = 8/(y -
4)
We'll divide by 8:
2/(x -
4) = 1/(y - 4)
We'll cross multiply and we'll
get:
x - 4 = 2y - 8
We'll keep
2y to the right side, moving -8 to the left:
x - 4 + 8 =
2y
2y = x + 4
y = x/2 +
2
Since we know now the equation of the line, we could tell
what other point lies on this line, replacing the coordinates x and y by the values of
the coordinates of the points.
We'll check if the point
(5,5) is on the line:
5 = 5/2 +
2
5 = (5+4)/2
5 = 9/2
impossible
Since LHS is different from RHS, the point is
not located on this line, y = x/2 + 2.
We'll verify the
point (6,6):
6 = 6/2 + 2
6 = 3
+ 2
6 = 5 impossible
As we can
see, (6,6) is not located on the line y = x/2 + 2.
We'll
check for (10,7):
7 = 10/2 +
2
7 = 5 + 2
7 =
7
The point (10,7) lies on the line y = x/2 +
2.
We'll check (14,8):
8 =
14/2 + 2
8 = 7 + 2
8 = 9
impossible
The point (14,8) is not on the line y = x/2 +
2.
We found the option C. (10 , 7) is
convenient in the given circumstances.
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