ok if im right we did this recently and if i remember you would do something like
21=2e+e
variables:
2e=math
e=english
1/2e=history
42=2x+x+1/2x+c
this should solve this one
x= first equations value for e
c= value for chem
21=2e+e >> 21/3=e >> e=7 hr
so history should be 4 hr
math 16hr
english 8hr
42=3.5+14+7+c
42-24.5=24.5-24.5+c
17.5=c
there for your answer is chem=17.5, english=7, math=14, history=3.5
this is at least how i was taught where i live last year

@StarlightDreams Thank you soooo much for your help, I just solve it by your help

@eldeablo666 thanks for your help also!! Your answers confirm that I wrote my equation right! Thanks!!!

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Screams from the haters, got a nice ring to it. I guess every superhero need her theme music...

it is
that's why I used "sets of points" instead of just "points"
too lazy to write t=-pi/3+2*k*pi (k=integer) XD

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its cold down here fam ~

It's a circle...

x=rcos(theta)
y=rsin(theta)

^I don't think I get what you're trying to say T_T
converting polar functions into rectangular ones before solving, maybe?

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its cold down here fam ~

Wait... you want the points in polar coordinates?

But... that's just the radius and the angle.

uhm...
you have a point there XD
guess I will rest the case here
wasted too much time already


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its cold down here fam ~

need ap calc help its a definite integral problem

its the one where there is a long "s" at the beginning of the equation



4
S 5/x (the 5/x is all in a radical sign)
1

(ln(x))' = 1/x
there you go sir


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its cold down here fam ~

if I read this right you want to integrate the function 5/x over the interval [1,4].and where is the problem?
build the stem-function and just ingerate it.since the interval is [1,4] you don't have to watch out for the symmetry of the graph.
the stem-function to 1/x = ln(x)

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Can anyone help me with this equation. This is venn diagram survey problems, but I can't solve it!

A survey is made of people, all of whom enjoy at least one of the activities music, painting and sculpture.

34% enjoys painting
18% enjoy both sculpture and painting
16% both sculpture and music
9% sculpture only
24% both painting and music
Twice as many enjoy painting as enjoy sculpture

Let n(FnGnL)=x
Draw a venn diagram and mark on it, in terms of x where neceesary the number of students represented by each region
Form an equation in x and solve it.

What percentage enjoy:
a) all three
b) just one of the three?

Can anybody please help me!! (i have been trying for the past 2 nights to find m=music )

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Screams from the haters, got a nice ring to it. I guess every superhero need her theme music...

Correct me if I'm wrong, but do those numbers not add up to 101%?

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I choose these variables:

m = likes music only
p = likes painting only
s = likes sculpture only
x = likes music and painting, but not sculpture
y = likes music and sculpture, but not painting
z = likes painting and sculpture, but not music
a = likes all three

Then, I represent the given statements with the following equations:

p + x + z + a = 34
z + a = 18
y + a = 16
s = 9
x + a = 24
p + x + z + a = 2 * (s + y + z + a)

I then begin simplifying the equations, starting with the last one:

p + x + z + a = 2 * (s + y + z + a)
34 = 2 * (s + y + z + a) {substitute using 1st equation}
17 = s + y + z + a {divide both sides by 2}
17 = 9 + y + z + a {substitute using 4th equation}
8 = y + z + a {subtract 9 from both sides}
8 = y + 18 {substitute using 2nd equation}
-10 = y {subtract 18 from both sides}

Since, by definition, percentages must fall within the range 0..100 inclusive, y cannot be -10, thus proving the 6 given statements, as written, to be in contradiction. There is no solution. Q.E.D.

thats the point.

the % contain overlap, so they should add up to 101+X% and that X% is well, your solution to the problem

So we got a Venn Diagram with 3 circles.
Painting Circle
Sculpture Circle
Music Circle.

I can't draw very well Here. but its got 7 parts that add up to 100%.

To find music, we look, Painting (34%) I assume includes P+PM+PS+X.

so 34+9 (sculpture only) is going to leave Music only and MS which is 16 %.

so whats left is 100-34-9 = 41% music only.

Course looking at the TWICE AS MANY PEOPLE ENJOY Painting as sculture, that would make the total for sculture 34/2 = 17 which is wrong.

so yeah, 34 is painting only. Blah... looks. those aren't %. those are people polled.

34 PEOPLE like painting only, out of like 150 people.

So anyways. we got for painting 34 + 18 +24 +X = 2(Sculpture) which is 9+18+16+X right?

so 76+X = 86 + 2X

Er... X would be -10 people.....

yeah the numbers aren't working. but if they were working I guess -10% for X and 9 for music only would solve the diagram, its just not a valid answer.

I have gotten -10 in class to but that cannot be the answer, we asked him and he told us that there is no mistakes in that equations.

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Screams from the haters, got a nice ring to it. I guess every superhero need her theme music...