1.Without using Pythagorus theorm, prove that the points (-4,-3), (-2,2),(8,-2)are the vertices of a right angled triangle.

2. The 3 vertices of a parallelogram taken in order are (3,4),(-2,3), (-3,-2).Find the coordinates of the fourth vertex ?

can u pl explain me in detail.

1 answer

how far have you gotten using Reiny's suggestion?

For #2, you might also look at it as involving the translation of one line onto a parallel line.

The line from (-2,3) to (3,4) is one side of the parallelogram.

If you translate (-2,3) to (-3,-2) then you have moved it by (-1,-5). So, move the other end of the line by the same amount, and you will have found the other end of the parallel side.