endpoints. basic geometry

[violet vale]

So we basically have to find the second endpoint but we’re only given the midpoint and one endpoint. I tried using the midpoint formula on one of the previous questions that were asking for the mid point…but it didn’t work so….

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[violet vale]

question 21 and 23 btw

[empty drift]

Well, I'm not really familiar with this kind of question. But since the problem gave you one endpoint and the middle point of a line, don't you just need to calculate the distance between one endpoint and the midpoint, double it and add to the first endpoint?

[soft patrol]

that is a way that works, but is longer and less efficient

[soft patrol]

let the other endpoint hold the coordinates (a, b)

[soft patrol]

can you find the midpoint in terms of a and b?

[violet vale]

How

[violet vale]

Would you have to put one of the coordinates on one side

But would it be the second end point coordinates or the midpoint coordinates

[velvet dune]

$(\frac{x_1+x_2}{2}, \frac{y_1+y_2}{2})$

[sacred spoke]

;(

[velvet dune]

midpoint formula

what would x_1 and y_1 be here?

[violet vale]

X_1 would be -1 and y_1 would be -8

[velvet dune]

yes

wait y=9

??

[soft patrol]

take the two endpoints, (-1, 9) and (a, b), and find the midpoint using them

then set it equal to the midpoint you are given

[violet vale]

Okay thanks