Question 1, 4 , 5 by Kang Yan

Q1. 

Based on the above conversation discuss, with examples and justification whether the following statement is justified.  'A square is a rhombus but a rhombus is not a square'.

A rhombus has 2 pairs of parallel lines and the length of all the sides are equal. A square has 2 pairs of parallel lines, the length of all the sides are equal and has 4 right angles. Since the properties of the square fall under the properties of the rhombus, the square is considered a special type of rhombus.

    

Source: http://www.analyzemath.com/Geometry/rhombus_problems.html

             http://mathforum.org/trscavo/tangrams/area-answers.html

Q4.

'All parallelograms are squares?' Do you agree with this statement?

Justify your answer with example/s.

No, I do not agree with this statement. Just like all surgeons are doctors but not all doctors are surgeons, all squares are parallelograms but not all parallelograms are squares. In order for a parallelogram to be a square as well, it must have 2 pairs of parallel sides, 4 right angles and 4 sides of equal lengths.

                  

Source: http://www.geometry-help.info/Area_of_a_Parallelogram.html

             http://mathforum.org/trscavo/tangrams/area-answers.html

Q5.

ABCD is a parallelogram. If E is midpoint of AD and  F is midpoint of BC show, with reasons, that BFDE must be a parallelogram.

If BFDE must be a parallelogram, its opposite sides must be of equal length and are parallel to each other. Since E is the midpoint of AD and F is the midpoint of BC, the length of BE should be the same as the length of DF and BE should also be parallel to DF. BF is confirmed parallel to DE. From all these reasons, BFDE must be a parallelogram.   

Maths Activity 3 - Michelle Lim.

Q2:

D. All of the above.

Both the square and parallelogram has 4 sides and 4 straight lines.

Since the square and parallelogram has 4 straight lines, the opposite sides will be parallel.

A trapezoid has the bottom and top line parallel.

Q3)

It should be a parallelogram, as, since they are parallel, the angles opposite each other will be the same, since 360 degrees makes a whole circle, which is also the whole shape, if the sum of one opposite side is equal to 180degrees, the whole parallelogram will be 360 degrees. So, it should be a parallelogram.

Q4) 

No, i disagree with this statement. A square has parallel lines. But, the whole shape must be the same length, however, in the parallelogram, the length can differ. So, in this case, the angles of the parallelogram can be different. But, the angle of the square remains as 90 degrees.

Question 2, 3 and 4 by Wee Ren Chang

Question 2

All statements are correct. For A, a square and parallelogram are all quadrilaterals as they have four sides, as what a quadrilateral should have. For B, the opposite sides of the square and parallelogram are parallel, therefore statement B is correct. For C, a trapezoid is what we learned in primary school as a trapezium. We have been taught that trapeziums have one pair of parallel sides which are at the top and the bottom of the trapezium.

Question 3

I think this quadrilateral is a trapezium where the length of the non parallel sides are equal. This trapezium fits into the description of the quadrilateral described.

Question 4

I disagree with this statement. Although a square is a parallelogram, as they have the properties of a parallelogram, the "common" parallelogram is a quadrilateral with two pairs of sides that are parallel to each other. However, the thing that differentiates the parallelogram from the square is the parallelogram's sides are not equal in length.

Source of images: http://en.wikipedia.org/wiki/Quadrilateral

Maths Activity 3-Kristin Chai

Q2: Answer is D.
The square and parallelogram are quadrilaterals as they are 4 sided which is correct.If the opposite sides of a square and a parallelogram are not parallel,they are not even squares or parallelograms and they will be other shapes.Also,they have a pair of parallel sides if not they will not look like a square or parallelogram.

Q3:It should be a parallelogram as a pair of opposite angles that are supplementary which is 180 degree as the parallelogram have a pair of parallel lines so the angels should be 180 degrees.Even though the other pair of length is not the same,the angels will still add up yo 180 degree.Thus,it is a parallelogram.

Q4: I do not agree with the statement as you see the parallelograms are titled.Even though the lines are parallel the 4 sides of the parallelogram is not the same and also the angels are not 90 degree.So parallelograms are not squares.

E learning Maths

Attached is my work

Eugene Liow

Math activity 3 (Q2, 3, 4)

Q2 Ans : D

     Quadrilaterals are a four-sided figure. Both the square and the parallelogram are four-sided figure, hence they are quadrilateral.

Then length of each side of the square are same, hence opposite sides of a square are parallel. The length of opposite side of the parallelogram are parallel to each other. Hence both the square and parallelogram have opposite sides that are parallel.

             

Q4 No I do not agree with this statement. A parallelogram is a quadrilateral with two pairs of parallel sides. Even though the square is like that, there are also other shapes that fulfill these points. A few examples are rhombus, trapezium and rectangle. 

Q5 The opposite sides are the same and parallel to each other. The adjacent angles adds up to 180 degrees and the opposite angles are the same.Therefore, we can conclude that it is a parallelogram.

108's CLASSIFICATION OF QUADRILATERALS