## ameryn.love17 3 years ago Three vertices of a parallelogram are (-3,4),(-5,8),(1,-6) what the fourth vertex

1. sasogeek

have you done vectors?

2. ameryn.love17

nope

3. agdgdgdgwngo

You can plot the points in the graph to visualize the problem better. One way to solve this problem is to compute the different slopes of the lines joining two vertices, using the point-slope formula $$slope = \frac{y_2-y_1}{x_2-x_1}$$ and then look for the one which does share a slope with other points.

4. sasogeek

|dw:1326156907260:dw| A(-3,4) B(-5,8) C(1,-6) find D

5. agdgdgdgwngo

Ultimately there will be three possible parallelograms you can make.

6. sasogeek

how?

7. agdgdgdgwngo

You can flip the triangle formed by the 3 given points in 3 different ways to get three different paralellograms.

8. sasogeek

there's actually only one if 3 points are given... 2 lines will be made from the 3 points, u only need parallel lines to intersect to find the forth point

9. sasogeek

why would u flip it? it points remain where they are i suppose...

10. sasogeek

i was going to use vectors to solve this though but you've got no idea about vectors.... hmmm :/

11. agdgdgdgwngo

You can make a paralellogram by drawing the reflection of the triangle across one of its sides.

12. agdgdgdgwngo