If x and y are numbers such that (x+5)(y-5)=0, what is the smallest possible value of x^2 + y^2 Choices:
A) 0
B) 4
C) 9
D) 25
E) 16
From (x+5)(y-5)=0 it follows that either x=-5 or y=5. Thus either x^2=25 or y^2=25.   Now, if x^2=8125, then the least value of y^2 is 0, so the least value of x^2 + y^2 = 25 + 0= 
<gadget id="calculator">25 + 0</gadget>
<output>25</output>
25.   Similarly if y^2=25, then the least value of x^2 is 0, so the least value of x^2 + y^2 = 0 + 25= 
<gadget id="calculator">0 + 25</gadget>
<output>25</output>
25.   Answer: 25.
<result>D</result>
If x and y are numbers such that (x+5)(y-5)=0, what is the smallest possible value of x^2 + y^2