If 4/(a + 5) = 7/(a - 4), then a = ? Choose the correct choice from the following:  A) -15  B) -19  C) -17  D) -18  E) -13
Multiply all terms of the given equation by (a + 5)(a - 4), simplify and solve   (a + 5)(a - 4)[ 4/(a + 5) ] = (a + 5)(a - 4) [ 7/(a - 4) ]   4 (a - 4) =7 (a + 5)   a = -17   correct answer -17
<result>C</result>
If 4/(a + 5) = 7/(a - 4), then a = ?