Question

Geometry question: How would I find the the other end-point and x?

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Answer 1

Use the midpoint formula

Answer 2

If the other end point has an x-coordinate 'x', then by midpoint formula, the x-coordinate of (18, -1) is average of that of (25, -5), so you get

\[ 18 = \frac{x + 25}{2} \]

Answer 3

Solving which, you get x = 11

Answer 4

M = (x1 + x1/2), (y1 + y2/1)

But isn't the midpoint formula:

Answer 5

The midpoint formula is \[ (x, y) = \left( \frac{x_1+x_2}{2}, \frac{y_1+y_2}{2} \right)\] and we have used only the x-coordinate part, that is, \[x=\frac{x_1+x_2}{2}\]

Answer 6

Okay...

So we are given (25, -5)(18, -1)

So...
x = x1 + x2/2
x = 25 + 18/2

That's what I would do, but you did something different. CAn you explain what you did?

Answer 7

Yes, that's because 'x' is not the x-coordinate of the midpoint, but that of an endpoint, so it actually goes in place of x2

Answer 8

I'm confused...

Answer 9

You need to see the arrangement of points

One end point: (25, -5)
Midpoint (18, -8)
Second end point: (x, y)

now if you apply the mid point formula, 18 should be the average of 25 and x, that is,
\[ 18 = \frac{25 + x}{2} \]

Answer 10

*sorry it's (18, -1)

Answer 11

What do you mean the average?

Answer 12

If you see the midpoint formula, it clearly is a formula for the average of the two end points; It states that the coordinates of the midpoint are the average of those of the end points.

Answer 13

Don't worry about the 'average', focus more on the position of points. You are solving it with (x, y) as a midpoint instead of (18, -1).

Answer 14

I could help you if you want my help and you don't runaway from me @Compassionate

Answer 15

Give you 5mins think about it I will be more than happy if you tag me.

Answer 16

YES!!!!!!!!! can I help you?