# Union and intersection

• May 18th 2011, 11:34 AM
haftakhan
Union and intersection
Question is that

If
A={parallelogram}
B={rectangle}
C={Squares}

Find AUB,B intersection C and A intersection C.

I want to know how to sole these questions ?
• May 18th 2011, 11:36 AM
abhishekkgp
Quote:

Originally Posted by haftakhan
Question is that

If
A={parallelogram}
B={rectangle}
C={Squares}

Find AUB,B intersection C and A intersection C.

I want to know how to sole these questions ?

true or false??:
1)every rectangle is a parallelogram.
2)every square is a rectangle.
3)every square is a parallelogram.
answer the above and then re-attempt.
• May 18th 2011, 11:40 AM
haftakhan
All are false
• May 18th 2011, 11:42 AM
abhishekkgp
Quote:

Originally Posted by haftakhan
All are false

well... i am pretty sure all are true.
define the following:
1)rectangle
2)parallelogram
• May 18th 2011, 11:48 AM
haftakhan
there shapes are different but yes both have a same thing that both have 2 equal parallel sides
• May 18th 2011, 11:50 AM
abhishekkgp
Quote:

Originally Posted by haftakhan
there shapes are different but yes both have a same thing that both have 2 equal parallel sides

what do you finally think?? were those statements true or false?
and you must be able to define each of the three shapes before attempting the problem.
would you like to try that and post it here??
• May 18th 2011, 03:17 PM
Soroban
Hello, haftakhan!

Quote:

$\text{Given: }\;\begin{bmatrix}A&=&\{\text{parallelograms}\} \\ B & = & \{\text{rectangles}\} \\ C &=&\{\text{squares}\} \end{bmatrix}$

$\text{Find: }\;(a)\;A\;\cup\,B \quad (b)\;B\,\cap\,C \qquad (c)\;A\,\cap\,C$

Consider the definitions of the three shapes.

. . Parallelogram: Quadrilateral with opposite parallel.

. . Rectangle: Quadrilateral with opposite sides parallel and right angles.

. . Square: Quadrilateral with opposite side parallel and right angles and all sides equal.

Note that:

. . {Parallelograms} includes Rectangles and Squares.

. . {Rectangles} includes Squares.

So we have:

. . $A \;=\;\{\text{parallelograms, rectangles, squares}\}$
. . $B \;=\;\{\text{rectangles, squares}\}$
. . $C \;=\;\:\{\text{squares}\}$

Now answer the questions . . .