If a - b = 3 and a^2 + b^2 = 35, find the value of ab.  Choose the correct choice from the following answers
A) 12 B) 13 C) 10 D) 18 E) 13
2ab = (a^2 + b^2) - (a - b)^2   = 35 - 9= 
<gadget id="calculator">35 - 9</gadget>
<output>26</output>
26   ab= 13.   Answer is 13.
<result>B</result>
If a - b = 3 and a^2 + b^2 = 35, find the value of ab.