Solving a Double Quadratic Equation: Finding n+m

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thereddevils
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Homework Statement



4n^2+9m^2-240n-720m+18000=0

Find n+m

Homework Equations





The Attempt at a Solution



I try to express the equation in the form of a(n+m)^2-b(n+m)+c=0 but i couldn't find a way to do so .
 
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The expression can be written in the form of 4(n-a)^2+9(m-b)^2=0


ehild
 
What calculations have you done so far? If you show what attempts you've made so far then can see how it's going. :smile:
 
Axiom17 said:
What calculations have you done so far? If you show what attempts you've made so far then can see how it's going. :smile:

Thanks for replying here , i hv got it solved.

Just express it in the form Ehild suggested and the values of m and n will be b and a respectively.
 
can someone pls show me the full step working?
 
cycy said:
can someone pls show me the full step working?

Do you know how to complete the square?
 
thanks for answering...
not really...
i'm just wondering how to get rid of the constant,18000,if we express it as 4(n-a)^2+9(m-b)^2=0
 
cycy said:
can someone pls show me the full step working?
Sorry, but at this forum that is not how we give help.

cycy said:
thanks for answering...
not really...
i'm just wondering how to get rid of the constant,18000,if we express it as 4(n-a)^2+9(m-b)^2=0
Try expanding that expression first. Then you can compare it to the original equation.
 
cycy said:
thanks for answering...
not really...
i'm just wondering how to get rid of the constant,18000,if we express it as 4(n-a)^2+9(m-b)^2=0

I wasn't answering anything, I was asking you a question. If you know how to complete the square then this problem isn't too difficult at all.

I just wanted to know where to start helping you, but I don't think you really deserve any unless you clean up your attitude mate.