Secondary 2 Maths
1 Answer
We have
\[500=(5x-5y)^2=(5x)^2+(5y)^2 -2\cdot (5 x)(5y)=25x^2+25y^2-50xy.\]
Since $xy=5$,
\[500=25x^2+25y^2-50xy=25x^2+25y^2-50\cdot 5=25x^2+25y^2-250\]
\[\Rightarrow 500+250=25x^2+25y^2\]
\[\Rightarrow 750=25(x^2+y^2)\]
\[\Rightarrow x^2+y^2=\frac{750}{25}=30.\]
![Savionf](https://matchmaticians.com/storage/user/100019/thumb/matchmaticians-3sehpu-file-1-avatar-512.jpg)
557
Join Matchmaticians Affiliate Marketing
Program to earn up to a 50% commission on every question that your affiliated users ask or answer.
- 1 Answer
- 186 views
- Pro Bono
Related Questions
- Help needed finding a formula
- Abstract Algebra : Commutativity and Abelian property in Groups and Rings
- Let $f(x,y,z)=(x^2\cos (yz), \sin (x^2y)-x, e^{y \sin z})$. Compute the derivative matrix $Df$.
- Solve this problem using branch and bound algorithm.
- Generating set for finitely generated submodule of finitely generated module
- Prove that $1+\frac{1}{\sqrt{2}}+\dots+\frac{1}{\sqrt{n}} \leq 2 \sqrt{n}-1$
- Fields and Galois theory
- Induced and restricted representation