If a - b = 3 and a2 + b2 = 29, find the value of ab.	Pick one
A) 10
B) 12
C) 13
D) 14
E) 15
2ab = (a2 + b2) - (a - b)2   = 29 - 9= 
<gadget id="calculator">29 - 9</gadget>
<output>20</output>
20   ab= 10.   10
<result>A</result>
If a - b = 3 and a2 + b2 = 29, find the value of ab.