The midpoint of AB is at (-1,-4). If A=(-5,-3), find B.?
回答 (3)
2016-04-13 5:02 pm
Let (x, y) be the coordinates of B.
x-coordinate of the mid-point :
(-5 + x)/2 = -1
-5 + x = -2
x = 3
y-coordinate of the mid-point n:
(-3 + y)/2 = -4
-3 + y = -8
y = -5
Coordinates of B = (3, -5)
x-coordinate of the mid-point :
(-5 + x)/2 = -1
-5 + x = -2
x = 3
y-coordinate of the mid-point n:
(-3 + y)/2 = -4
-3 + y = -8
y = -5
Coordinates of B = (3, -5)
2016-04-13 5:04 pm
i) Let B be (x, y)
ii) Then midpoint of AB is: ((-5+x)/2, (-3+y)/2) = (-1, -4)
==> (-5+x)/2 = -1; so -5 + x = -2
Solving x = 3
Similarly, (-3 + y)/2 = -4; so -3 + y = -8
Solving, y = -5
Thus B is (3, -5)
ii) Then midpoint of AB is: ((-5+x)/2, (-3+y)/2) = (-1, -4)
==> (-5+x)/2 = -1; so -5 + x = -2
Solving x = 3
Similarly, (-3 + y)/2 = -4; so -3 + y = -8
Solving, y = -5
Thus B is (3, -5)
2016-04-13 5:02 pm
B: (3,-5)
from point Ax to midpoint is 4 spaces, so add -1+4=3
from point Ay to midpoint is -1, so subtract -4-1=-5
from point Ax to midpoint is 4 spaces, so add -1+4=3
from point Ay to midpoint is -1, so subtract -4-1=-5
收錄日期: 2021-04-18 14:49:52
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