Add.

start fraction a over a plus 3 end fraction plus start fraction a plus 5 over 4 end fraction

A. start fraction 4 a plus 20 over left parenthesis a plus 3 right parenthesis times left parenthesis a plus 5 right parenthesis end fraction


B. start fraction a squared plus 12 a plus 15 over 4 times left parenthesis a plus 3 right parenthesis end fraction


C. start fraction a squared plus 19 a plus 8 over 4 times left parenthesis a plus 3 right parenthesis end fraction


D. start fraction 4 a squared plus 19 a plus 8 over 4 left parenthesis a plus 3 right parenthesis end fraction

The answer is B.

To add fractions with different denominators, we need to find a common denominator. In this case, the common denominator is 4(a+3):

start fraction a over a+3 end fraction + start fraction a+5 over 4 = start fraction 4a over 4(a+3) end fraction + start fraction a+3(a+3) over 4(a+3) end fraction

Now we can combine the numerators:

start fraction 4a + a(a+3) + 5(a+3) over 4(a+3) end fraction

Simplifying the expression:

start fraction a^2 + 12a + 15 over 4(a+3) end fraction

Therefore, the answer is B.