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# Really stuck need maths genius

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1. Hi
My name is physicsmaths.
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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2. 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?

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?
3. (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?

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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4. (Original post by surina16)
What is funny.

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

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That's the quadratic formula. I don't know how to write in the fancy fractions that you can do, so I used brackets
7. (Original post by physicsmaths)
Hi
My name is physicsmaths.
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

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
8. BTW, I find the answers to be:

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

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
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?
10. (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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11. (Original post by Ayman!)
hi physicsmaths

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
Omds. That is so genius.
Thanks

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12. Just noticed the radius is
Nice touch, OP
13. The reference is lost on me.
14. (Original post by SeanFM)
The reference is lost on me.
Long time no see

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15. (Original post by RDKGames)
Nice touch, OP
Is ur radius bigger then mine

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16. (Original post by physicsmaths)
Is ur radius bigger then mine

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Latex fail. Nah fam, simply the same
17. (Original post by Ayman!)
hi physicsmaths

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
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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18. (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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19. (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: so

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