Question

finding missing endpoints: is there a way to do it algebraically?
http://www.youtube.com/watch?v=d51p_8xQQZ0
so you can draw a number line to see how far each number is from each other, but is there a faster way to do it?

Answer 1

ignore this video. you can find the endpoint using algebra or just thinking. you have an actual problem to solve?

Answer 2

Endpoint: (−9, −1), midpoint: (8, 14)

Answer 3

you want algebra or think method?

Answer 4

algebra

Answer 5

or whatever you were typing

Answer 6

we can do both
for first coordinate solve
\[\frac{x-9}{2}=8\] and for second solve
\[\frac{y-1}{2}=14\]

Answer 7

because midpoint you use
\[\frac{x_1+x_2}{2}\] for the first coordinate and
\[\frac{y_1+y_2}{2}\] for the second. so if you know the answer you can find the first or second coordinate

Answer 8

oh i see i got it right, you subtracted because they're negative?

Answer 9

thank you :'}
you're very good at math don't ever stop what you're doing

Answer 10

yes i "subtracted" because both were negative. if they had been positive i would have added.

Answer 11

thank you for the compliment