The product of a and b is equal to 1 more than twice the sum of a and b. If b = 7, what is the value of b - a?
Pick:  A) 2  B) 5  C) 4  D) 24  E) 35
ab= 1 + 2(a+b)   7a= 1+2a +14   5a= 15   a=3   b-a= 7-3= 
<gadget id="calculator">7-3</gadget>
<output>4</output>
4   4 is the answer
<result>C</result>
The product of a and b is equal to 1 more than twice the sum of a and b. If b = 7, what is the value of b - a?