The sum of squares of three numbers is 764 and sum of their products taken two at a time is 500. What is their sum?  Choose one:
A) 48
B) 42
C) 52
D) 32
E) 33
Description :   Let the numbers be x,y,z.   =&gt; x2+y2+z2=764   =&gt; 2(xy+yz+xz)=2*500= 
<gadget id="calculator">2*500</gadget>
<output>1_000</output>
1000=&gt; (x+y+z)2=(x2+y2+z2)+2(xy+yz+xz)=1764   =&gt; (x+y+z)=sqrt(1764)=42   Answer 42
<result>B</result>
The sum of squares of three numbers is 764 and sum of their products taken two at a time is 500. What is their sum?