Question

Look at the photo frame.
Which statement is true about the photo frame?

A.) It is exactly rectangular because sides BC and DC meet at a right angle.

B.) It is exactly rectangular because the width is greater than the length.

C.) It is not exactly rectangular because the sides BC and DC form an acute angle.

D.) It is not exactly rectangular because the diagonal is greater than the sum of the length and width.

Answer 1

@Robb828 do you know Pythagoras theorem?

Answer 2

yes i do

Answer 3

Check if BDC is a right triangle?

Answer 4

how do i determine wich is A B and C

Answer 5

It doesn't matter if the width's greater than the length. They're just names.
You'll have to consider the angle that's being formed by the sides.
A rectangle has 2 pairs of parallel lines and there's also 2 pairs of perpendicular lines. perpendicular lines form 90 degrees. So what's the answer?

Answer 6

@Robb828 First find the largest side, its square should be equal to the sum of the squares of the other two sides. No need to find which is a, b or c. Do you get my point?

Answer 7

not really

Answer 8

OK, I'll give you an example.
Here I don't know which is a or b or c. I'll look for the largest side. 5 is the largest side. Its square should be equal to the sum of squares of the other two sides
\[5^2=3^2+4^2\]\[25=9+16\]
so this triangle is a right triangle, now you check if BCD is a right triangle

Answer 9

oh ok thanks for breaking it down

Answer 10

i got 169=169

Answer 11

Yeah so it's a right triangle. That means BC and DC meet a right angles. What do you infer from that

Answer 12

its not C

Answer 13

Good!! So what is ABCD, rectangle or a quadrilateral

Answer 14

Rectangle

Answer 15

Hod do you infer that?

Answer 16

*how?

Answer 17

Because both triangles equal the same amount

Answer 18

What about the angles?

Answer 19

They are equal to

Answer 20

Ok tell me one thing what's a rectangle?

Answer 21

it has four right angles

Answer 22

You're right and what about the sides?

Answer 23

opposite sides are parallel

Answer 24

Wow I didn't think about that. What about the sides' dimensions?

Answer 25

im not dure what those are

Answer 26

sure*

Answer 27

Opposite sides are equal but neighboring sides aren't. Check if that's satisfied here!!

Answer 28

yes it seems as if they are

Answer 29

SO what's you r inference now? What type of figure is ABCD?

Answer 30

a rectangle

Answer 31

Yeah, You're right.
Did you understand the problem's solution?

Answer 32

yes i understand it much better now :) so its A

Answer 33

Yeah!

Answer 34

Thank you so much :)

Answer 35

You're welcome:D