Library / /20 of 520
Algebra Difficulty 2.2 Junior Find the answer
Given x2+y2+4x−6y+13=0, find the value of xy.
A number or a short expression. Spacing and $ signs are ignored.
Solution
Transform the given equation to get: (x+2)2+(y−3)2=0,
thus x+2=0, y−3=0, which means x=−2, y=3,
therefore, xy=(−2)3=−8.
So, the value of xy is −8.
Want a route through all this instead of an archive?
The track
puts 2,000 problems in a working order, from AMC 10 level to the IMO shortlist.
Source: NuminaMath-1.5,
licensed Apache-2.0.
Statement and solution reproduced as published; topic and difficulty added by this site.