Each writer for the local newspaper is paid as follows: a dollars for each of the first x stories each month, and a + b dollars for each story thereafter, where a > b. How many more dollars will a writer who submits x+ a stories in a month earn than a writer who submits x+ b stories? Answers
A) (a – b)( a + b + x)  B) a – b  C) a^2 – b^2  D) x( a – b)  E) ax + bx – ax
total earned for x+a stories =a + a(a+b)   total earned for x+b stories =a+ b(a+b)   difference = a+a(a+b) -a -b(a+b)   =(a+b)(a-b) =a^2-b^2   answer is a^2 – b^2
<result>C</result>
Each writer for the local newspaper is paid as follows: a dollars for each of the first x stories each month, and a + b dollars for each story thereafter, where a > b. How many more dollars will a writer who submits x+ a stories in a month earn than a writer who submits x+ b stories?