Monday, December 04, 2006
posted by christine at 5:02 p.m.
Friday, December 01, 2006

In class, we did an exercise were we had to decide whether point A(5,2), point B(1,9), point C(-3,2) and point D(1,-5) is a rectangle, rhombus, a square or a parallelogram.

First, we figure out the distance of AB, AD, DC, and BC by using the distance formula.

By doing the same thing, we found out that the distance of AD, DC, and BC are all

which means that the diagram can not be a parallelogram or a rectangle because all 4 sides are equal length. A parallelogram and a rectangle only have equal opposite sides.

Secondly, we can also find the slope of the line to figure out if the diagonals are perpendicular to each other by using the slope formula.

By doing that we figured out that the diagonals are not perpendicular to each other, therefore it can not be a square or a rectangle.
Which leaves us with a RHOMBUS.

And don't forget about our homework, Exercises 28 and 31.

And by the way, sorry for posting last fridays lesson late.

Monday, December 04, 2006

For todays class, it started by Ms. Armstrong reminding us about couple of things. Then we started our lesson by doing a little activity to prepare us for our Trigonometry/ Geometry Test which is on Wednesday.
Todays activity was a green worksheet, were we had to choose whether the following statements were True or False.
1.) The consecutive angles of a parallelogram are congruent.
2.) Opposite angles of a parallelogram are congruent
3.) A rhombus has 4 congruent sides.
4.) A rectangle has congruent diagonals.
5.) If a quadrilateral is a rectangle, then it is a parallelogram.
6.) If a quadrilateral is a square, then it is a rhombus.
7.) If a parallelogram is a rectangle, then it is a rhombus.
8.) If a quadrilateral is a parralelogram, hten it is a rhombus.
Then at the bottom of the paper was a word problem that Ms. Armstrong will post seperately and everybody will have to work together through the blog to figure out the answer.