Question

Check my answer for an area problem. I want to make sure I have the correct value.

Answer 1

656.25

Answer 2

@freckles

Answer 3

so the area of regular polygon can be calculated doing
\[\frac{ \text{ length of one side } \cdot \text{ number of sides } \cdot \text{ apothem }}{2}\]

Answer 4

and we have two of these in the pic
\[\frac{17 \cdot 5 \cdot 11.7}{2} \\ \text{ but again we have two of these } \\ \\ \text{ so we have } 2 \cdot \frac{17 \cdot 5 \cdot 11.7}{2}\]
but then we also need to take into account the 5 rectangles there

Answer 5

did I do something wrong I got a number way bigger than your number

Answer 6

No, I entered the values incorrectly. I got 994.5

Answer 7

ok so the base of one of those rectangles is 17 km and we already know the height of one of the rectangles is 6 km

Answer 8

and we have 5 congruent rectangles

Answer 9

we also know we can find the area of a rectangle be doing base*height

Answer 10

so you will find the total surface area by calculating:
\[2 \cdot \frac{17 \cdot 5 \cdot 11.7}{2} +5 \cdot 17 \cdot 6\]

Answer 11

1504.5 :)!

Answer 12

the weird thing is that apothem measurement they gave doesn't seem to fit the formula for a regular polygon

Answer 13

\[\frac{17}{2 \cdot \tan(\frac{180}{5})} \neq 11.7\]

Answer 14

I believe the area of a pentagon formula can be used.

Answer 15

The final step I have to do is round the value to nearest hundredth...... 1504.5---> 1500.0

Answer 16

your answer is right even though I believe this is a false regular polygon

Answer 17

nearest hundredth!

Answer 18

not hundred

Answer 19

1504.50

Answer 20

the answer we have is 1504.5
so rounded to nearest hundredth is 1504.5 still

Answer 21

Alright.

Answer 22

1504.50 is same as 1504.5

Answer 23

Thank you so much for the help, @freckles!!! :)

Answer 24

did you get the problem right? just wondering because I'm confused about its given apothem measurement

Answer 25

Unfortunately I wasn't given any answer choices :(

Answer 26

oh ok

Answer 27

I have no way of determining until I finish the written test.

Answer 28

@sparrow2

Answer 29

did you guys ever use trig functions like tan( )?

Answer 30

Yes

Answer 31

what's the problem?

Answer 32

you are doing well

Answer 33

i hope :)

Answer 34

Do you agree with freckles method for solving this?

Answer 35

give me sec

Answer 36

@sparrow2 the problem is there measurement for the apothem doesn't match up with the definition for a regular polygon

Answer 37

even though they are making it seem like this is a regular polygon

Answer 38

by having all congruent sides and congruent angles

Answer 39

why it doesn't match?

Answer 40

\[\frac{17}{2 \cdot \tan(\frac{180}{5})} \neq 11.7 \]

Answer 41

surface area still?
well you have 3 congruent triangles
and another triangle which isn't congruent to the other 3 that being the base triangle

Answer 42

area of triangle equals a half of the base * height

Answer 43

it'c correct i think

Answer 44

but what about the apothem measurement ? you agree it is not a true polygon right @sparrow2

Answer 45

tg36=0.72 it approximetly

Answer 46

you should insert approximate measurment in tg36

Answer 47

of course it will not be exact meaning

Answer 48

oops lol the only calculator I have is wolfram and I forgot to type degrees
i'm sorry that was a true polygon and a true regular polygon to be more exact
so yes that was totally the correct answer

Answer 49

Don't worry freckles... :)

Answer 50

Could you help me with the next problem?