Question

Find the value of x. The diagram is not draw drawn to scale.

Answer 1

The sum of the measures of the interior angles of a polygon... you know them?

Answer 2

A triangle, for instance;
No matter how weird or deformed-looking the triangle, the sum of the measures of its interior angles is always 180°, right?

Answer 3

is it?

Answer 4

(n-2) x 180 ?

Answer 5

Oh, lol, yeah :D
A polygon of n sides can be neatly divided into n-2 triangles, each of which (sort of) contributes 180° of angle measure :D [Probably a wrong way to see it, but meh]
So yeah, (n-2) x 180°
Which amounts to
540° in the case of this pentagon.
Can you do it from here?

Answer 6

i get that part. i dont get what i do with the 540 lol . to find the answer

Answer 7

50 degress is the ans

Answer 8

Well, if you add up all the angle measures given (Don't forget that that lower left corner is a right angle! ), it should sum up to 540°. Then it's just algebraic manipulation :D

Answer 9

A. 35
B. 145
C. 90
D. 45
Theres not a 50.

Answer 10

i need to work back

Answer 11

Yeah, add them up
112 + 148 + 90 + x + (3x + 10) = 540
Work from there

Answer 12

so its 90 ?

Answer 13

Let's take it slow :D
Adding up the constants, you get
4x + 360 = 540

Answer 14

so you get 180 and divide 4 and so itss 45 ? (:

Answer 15

That's right :D

Answer 16

yay! thank you

Answer 17

No problem :D

Answer 18

so what if its a parallelogram ? thats my next one .

Answer 19

A. x = 21; y = 56; z = 103
B. x = 56; y = 21; z = 103
C. x = 56; y = 56; z = 124
D. x = 21; y = 56; z = 124

Answer 20

Well, for now, I feel like exploiting the fact that it's a multiple choice question, and let's eliminate the obviously wrong ones :D
You see the angle that measures z° ?

It's opposite an angle that measures 103°
What do we know about opposite angles in parallelograms?

Answer 21

B

Answer 22

y+21+103=180

Answer 23

interior angles are same .so x=21

Answer 24

there always congruent

Answer 25

That's right. So z = 103°, right?

Answer 26

yess

Answer 27

i got that but i have another one ): its different . i dont get this one at all . ;lol

Answer 28

Now, take a look at the parallell lines on the top and bottom (the pair with only one arrowhead apiece) The angle that measures x° and the angle that measures 21° are...?

Answer 29

ya

Answer 30

*parallel
sorry, bit of a perfectionist when it comes to typographical errors :D

Answer 31

For the parallelogram, if angle 2= 3x-28 and angle 4 = 2x-12 find angle 3 .The diagram is not drawn to scale.

Answer 32

By the way, the answer to the previous parallelogram problem is A, not B, ok?
If you're sure you understand that, then let's move on :D

Answer 33

okay!

Answer 34

Right, once again, in your parallelogram, angle 2 and angle 4 are opposite each other. What do we know about opposite angles in parallelograms? They are congruent. So their angle measures must be equal. Work from there :)

Answer 35

A. 20
B. 16
C. 160
D. 170

Answer 36

Your angle 2 measures 3x - 28
and angle 4 measures 2x - 12
But their measures must be equal, so
3x - 28 = 2x - 12

Answer 37

im still confused. lol

Answer 38

Well, for now, just work out the value of x in the equation I gave you.

Answer 39

1x

Answer 40

or 5x

Answer 41

No, I meant work out the value of x.