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Solve the equations: m² + n2 = 29; m + n= 7

User IamK
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1 Answer

2 votes

We have the following:


\begin{gathered} m^2+n^2=29 \\ m+n=7;m=7-n \end{gathered}

replacing:


\begin{gathered} (7-n)^2+n^2=29 \\ 49-14n+n^2+n^2=29 \\ 2n^2-14n+20=0 \\ n^2-7n+10=0 \\ (n-5)\cdot(n-2)=0 \\ n-5=0=>n=5 \\ n-2=0=>n=2 \end{gathered}

solving for n:

n = 5

n = 2

replacing:


\begin{gathered} m=7-5 \\ m=2 \\ m=7-2 \\ m=5 \end{gathered}

The solution is:

(2, 5) and (5, 2)

User Eugen Timm
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