All Answers

+118728

scartissue13:
(1.3-0.7j)+(3.6+2.4j)=?

Any help would be so awesome! Thank you.xx

fitrstly the brackets are meaningless

1.3 - 0.7j + 3.6 +2.4j

1.3 +3.6 - 0.7j + 2.4j

4.9 + 1.7j

MelodyFeb 28, 2014

+118728

lila7339:
In an alternating-current circuit, the voltage E is given by E=IZ, where I is the cirrent (in A) and Z is the impedance.

If I=0.729-0.139j amperes and Z=260+110j ohms, find the complex-number representation.
E=

E = (0.729 - 0.139j) (260+110j)

= 189.54 - 15.29*-1 + 30.69j - 36.14j

= 204.83 - 5.45j

I think that is alright but I could have made a stupid mistake - you had best check it.

MelodyFeb 28, 2014

+118728

hiijustwanthelp:
what is h (x) = log (x + 4)

It is just an equation. It is not a question.

MelodyFeb 28, 2014

+118728

New:
Im using the Pythagorean thermo to solve for triangles but a I want to know this 10=x times squareroot 3 what do I do, do I divide and 10 squareroot 3 = x?

10 = x * sqrt(3)

You have to divide both sides by sqrt(3) to get the x by itself.

so yes

x = 10 divided by sqrt(3)

10/sqrt(3)=

MelodyFeb 28, 2014

+118728

wowmaries:
How many different sums are possible for the numbers 4,2,3,7,3,4,6,5

Hi Wowmaries,
You have a time consuming question here!

2,3,3,4,4,5,6,7
3,3,4,4, pus 4 that are different

I am assuming that a 'sum' is referring to addition.
Add 2
3,3, 1 possibility
4,4, 1 posibility
both different 6C2
no of ways = 1+1+15 = 17

Add 3
3,3,plus another = 5
4,4 plus another = 5
all different = 6C3
no of ways = 5+5+20 = 30

Add 4
3,3,4,4, = 1
3,3, + 2diff = 5C2
4,4, + 2diff = 5C2
all diff = 6C4
no of ways = 1+10+10+15 = 36

Add 5
3,3,4,4, plus 1 diff = 4
3,3, plus 3diff = 5C3
4,4, plus 3 diff = 5C3
5 diff = 6C5
no of ways = 4+10+10+6 = 30

Add 6
3,3,4,4,plus 2 diff = 4C2
3,3,plus 4 diff = 5C4
4,4,plus 4 diff = 5C4
6 diff = 1
no of ways = 6+ 5+5+1 = 17

Add 7
3,3,4,4, plus 3 diff = 4C3
3,3,plus 5 dff = 1
4,4,plus 5 diff=1
no of ways = 4+1+1 = 6

Add 8
All of them =1

Grand total = 17+30+36+30+17+6+1 = 137
I may have made a stupid mistake but I think my technique is correct.

MelodyFeb 28, 2014

+118728

???????????????:
how long can you do math

All my life

It's cool

MelodyFeb 28, 2014

Moalin:
what is the easiest way to get sin, cos and tan without using Scientific calculator

Get a chart off the internet

GuestFeb 28, 2014

+6252

Quote:
The width of a sign is 1/5 times the length, and the total area of the sign is 200 square in.
What is the length and width of the sign?

width = length/5

area = length * width = length * length/5 = length ²/5 = 200

length ² = 5*200 = 1000

length = sqrt(1000) = 10*sqrt(10)

width = length/5 = 2*sqrt(10)

RomFeb 28, 2014

+6252

maybe, if you tell us what it is...

RomFeb 28, 2014

+118728

ANDREA:
6.2km to 7.4km ?

Do you want the ratio?

6.2 : 7.4
62 : 74
31 : 37
and that is as simple as it gets.

MelodyFeb 28, 2014

+118728

patrick:
If x = 5.9, and y = 14.6, what is theta? I though to use Tan (0) = 14.6/5.9, so Tan(0) = 7.05, but I can't remember how to use the calculator to figure this. Can you show me?

hi Pattrick,
Thatmathguy has given you a good explanation. thank you Thatmathguy
i just wanted to add to ito a little.

If you look at tan on your hand held calc you will see that above the button in a different colour is tan ^-1.
To bring that function up you have to press A SHIFT or 2ND button at the top of the calc.
That means you press
2nd tan (14.6/5.9) = 68 degrees

inverse tan can also be written as arctan
that is
tan ^-1(14.6/5.9) = atan(14.6/5.9)
this is how you get it on the site calc (you have to use the brackets even if it was just one number inside)

atan(14.6/5.9)=

MelodyFeb 28, 2014

+118728

Mahmoud1:
if you bought a share of stock for $2.50 per share and now it is $1.80, what is the percent of your loss?

loss = 2.50 - 1.80 = 0.70

%loss is always (unless told otherwise) actual loss / original cost = 0.7 / 2.50 * 100%

MelodyFeb 28, 2014

+118728

telliott412:
-4c(-9c^2+5c+8)

Hi telliott4,
i assume you want to expand this?
36c ³ - 20c ² -32c

hi guest.
Thank you for giving it a shot.
The hat ^ means 'power of'

So -9c^2 means -9c ² = -9*c*c

On computer sites * is used for multiply so that it doesn't get confused with x which is a letter commonly used in algebra.

To put 3 ² onto this page i would press
3 and then the 'sup' button that is located above the smilies. The curser will go where you need to put the 2. Then move the curser to the end and keep going.
If you use this notation it is much easier to read and leads to less confusion.
Thank you
Melody.

MelodyFeb 28, 2014

+118728

Cynthia:
The table shows the cost y (in dollars) of x pounds of sunflower seeds.

Write a linear function that represents the cost of y of x pounds of seeds.Interpret the slope.

Pounds,x Cost,y
2 2.80
3 4.20
4 5.60