Question

Let x, y be real variable satisfying the $x^2+y^2+8x-10y-40=0$. Let $a=max\left\{\sqrt{(x+2^2)+(y-3{)}^2}\right\}$ and $b=min\left\{\sqrt{(x+2^2)+(y-3{)}^2}\right\}$, then

• A. a + b = 18
• B. $a+b=4\sqrt{2}$
• C. $a-b=4\sqrt{2}$
• D. a, b = 73

Answer 1

Answer: (A), (C), (D)

The correct options are
A a + b = 18
C $a-b=4\sqrt{2}$
D a, b = 73