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Really stuck need maths genius

Hi
My name is physicsmaths.
I am stuck on maths question it is much very hard please help.
K so
ok so
they say to me
y=6x+3
and y^2+x^2=600
then they say it meets but how come it meets what if circle is so big it doesnt meet?
So i plug it in and get some next messed up quadratic equation with number infront of x^2 which idk wtf to do cause normally no number infront.
So basically
What do i do when there is number infront of x^2 in quadratic equation.


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So if im understanding this right, you're worried about a number in front of the x^2 in a quadratic equation when trying to solve it?
i.e. your quaradtic equation is:

y=a*x^2+b*x+c

Just put the relevant values into (-b +- sqrt(b^2-4*a*c))/(2*a)

Or am I being stupid?
:rofl:
Original post by Cheesy Taters
So if im understanding this right, you're worried about a number in front of the x^2 in a quadratic equation when trying to solve it?
i.e. your quaradtic equation is:

y=a*x^2+b*x+c

Just put the relevant values into (-b +- sqrt(b^2-4*a*c))/(2*a)

Or am I being stupid?

Yehyeh stuff like
36x^2 .... Etc=0
Whattt
What formula is that.
That is crazy



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Original post by surina16
:rofl:


What is funny.



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Wolfram alpha it, seems impossible indeed.
Original post by physicsmaths
Yehyeh stuff like
36x^2 .... Etc=0
Whattt
What formula is that.
That is crazy



Posted from TSR Mobile


That's the quadratic formula. I don't know how to write in the fancy fractions that you can do, so I used brackets :s-smilie:
Reply 7
Avatar for Ayman!
Ayman!
15
Original post by physicsmaths
Hi
My name is physicsmaths.
I am stuck on maths question it is much very hard please help.
K so
ok so
they say to me
y=6x+3
and y^2+x^2=600
then they say it meets but how come it meets what if circle is so big it doesnt meet?
So i plug it in and get some next messed up quadratic equation with number infront of x^2 which idk wtf to do cause normally no number infront.
So basically
What do i do when there is number infront of x^2 in quadratic equation.


Posted from TSR Mobile


hi physicsmaths :smile:

the question is very very hard but i think this is what you do you have x^2 + y^2 = 600 so if you square root both sides you get x + y = 600^1/2. now it's just simultaneous equations. hope that helps :biggrin:
BTW, I find the answers to be:

x = sqrt(87468)/74 or -1*sqrt(87468)/74
Original post by Ayman!
hi physicsmaths :smile:

the question is very very hard but i think this is what you do you have x^2 + y^2 = 600 so if you square root both sides you get x + y = 600^1/2. now it's just simultaneous equations. hope that helps :biggrin:


Wouldn't it be simpler just to square the equation y = 6*x + 3 to get y^2 = 36*x^2 + 9 and then equate that to y^2 = 600 - x^2 and solve for x?

Or is that wrong?
Original post by physicsmaths
Yehyeh stuff like
36x^2 .... Etc=0
Whattt
What formula is that.
That is crazy



Posted from TSR Mobile


That formula is the quadratic formula that can be used to solve any solvable quadratic. It is especially useful when it doesn't factorise or you are struggling to factorise it because of a coefficient in front of the x^2 term.


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Original post by Ayman!
hi physicsmaths :smile:

the question is very very hard but i think this is what you do you have x^2 + y^2 = 600 so if you square root both sides you get x + y = 600^1/2. now it's just simultaneous equations. hope that helps :biggrin:


Omds. That is so genius.
Thanks


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Just noticed the radius is 600\sqrt{600} :rofl:
Nice touch, OP
(edited 7 years ago)
The reference is lost on me.
Original post by SeanFM
The reference is lost on me.


Long time no see :smile:


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Original post by RDKGames
Just noticed the radius is 600\sqrt600 :rofl:
Nice touch, OP


Is ur radius bigger then mine


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Original post by physicsmaths
Is ur radius bigger then mine


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Latex fail. Nah fam, simply the same :smile:
Original post by Ayman!
hi physicsmaths :smile:

the question is very very hard but i think this is what you do you have x^2 + y^2 = 600 so if you square root both sides you get x + y = 600^1/2. now it's just simultaneous equations. hope that helps :biggrin:


The square root of x^2 + y^2 is not x + y

Try it, 64 + 36 = 100 the square root is 10. It is not 8 + 6


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(edited 7 years ago)
Original post by Cheesy Taters
Wouldn't it be simpler just to square the equation y = 6*x + 3 to get y^2 = 36*x^2 + 9 and then equate that to y^2 = 600 - x^2 and solve for x?

Or is that wrong?


That's wrong (6x+3)^2 = (6x+3)(6x+3), expand the brackets


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Original post by gdunne42
That's wrong (6x+3)^2 = (6x+3)(6x+3), expand the brackets


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Huh? Mate you need to check your maths: (a+b)2=a2+b2(a+b)^2=a^2+b^2 so a+b=a2+b2=a+ba+b=\sqrt{a^2+b^2}=a+b
(edited 7 years ago)

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