Question

Please answer:

1. Determine whether a triangle can be formed with the given side lengths. If so, use Heron's formula to find the area of the triangle.

a = 240
b = 132
c = 330

answers:

No triangle is formed.

30,776.84

13,385.87

30,790.94

2. Express the complex number in trigonometric form.
-4i

answers:
4(cos 180° + i sin 180°)

4(cos 270° + i sin 270°)

4(cos 90° + i sin 90°)

4(cos 0° + i sin 0°)

3. Find a ⋅ b.
a = 6i - 6j, b = 4i + 2j

answers:
12

-36

<24, -12>

<10, -4>

Answer 1

which one you want to do?

Answer 2

start with any please

Answer 3

k lets do the first one

Answer 4

you can definitely form a triangle with this, since the sum of any two sides is larger than the third
now we can find the area

Answer 5

first we need \(s=\frac{a+b+c}{2}\)
in your case you get
\[s=\frac{240+ 132+ 330 }{2}\] and a calculator

Answer 6

i get \(s=351\)
not done yet though

Answer 7

now we get
\[A=\sqrt{s(s-a)(s-b)(s-c)}\] which in your case is
\[\sqrt{351(351-24)(351-132)(351-330)}\]

Answer 8

think i lost @lanybug96

Answer 9

im here! just putting together what you did

Answer 10

ok good

Answer 11

this is heron's formula \(A=\sqrt{s(s-a)(s-b)(s-c)}\) where \(s=\frac{a+b+c}{2}\)

Answer 12

i would use a calculator, and i get this
http://www.wolframalpha.com/input/?i= \sqrt{351%28351-240%29%28351-132%29%28351-330%29}

Answer 13

made a typo there, put 24 where it should have been 240\[\sqrt{351(351-240)(351-132)(351-330)}\]

Answer 14

maybe this link works better
http://www.wolframalpha.com/input/?i=sqrt%28351%28351-240%29%28351-132%29%28351-330%29%29

Answer 15

go with 13,385.87

Answer 16

let me know if you want to do the next one too

Answer 17

yeah okay that's what I got! :)

Answer 18

good

Answer 19

here the absolute value is pretty clearly 4, and in any case all your answers have a 4 out front
all you need is the angle

Answer 20

that angle i hope is obvious, it is \(270\) since you are working in degrees

Answer 21

thank you so much

Answer 22

that tells you \(4i\) can be written as
\[ 4(\cos (270°) + i \sin (270°)) \]

Answer 23

oops i meant \(-4i\)

Answer 24

yw

Answer 25

you good with the dot product?

Answer 26

yeah the last one I need help on to plz

Answer 27

it is \(6\times 4+(-6)\times 2\)

Answer 28

i get \(12\)

Answer 29

your a life saver, thank you

Answer 30

yw
hope the method is clear in case you have to take a test or something
these problems are kind of all over the map
i assume it is an on line class