(2012 Green Bay Packers season)The Texans came into their first ever appearance on Sunday Night Football facing playoff favorites Green Bay, who had shockingly started the season 2-3, one of those losses ending in controversy.  And coming off another disappointing loss to Indianapolis the week before, the Green Bay Packers took out all of their early season frustrations out on the Texans at Reliant Stadium, and at the same time, reestablished themselves as the team to beat in the NFC.  Aaron Rodgers tore up the Texans defense with 6 touchdown passes, and the Packers as the Texans dropped to 5-1 and 0-1 on Sunday Night Football. On the second drive of the game, Aaron Rodgers threw a touchdown to James Jones to make it 7-0. A few drives later it was 14-0 on a Rodgers to Jones touchdown. Houston scored 1 drive later on an Arian Foster touchdown run to make it 14-7. Then Rodgers hit Jordy Nelson to make it 21-7. Before the half ended, Houston got a field goal to make it 21-10 at the half. Mason Crosby made a field goal but was nullified by Houston being offsides. Rodgers then hit Nelson to make it28-10. Foster scored again to make it 28-17. On the next drive, Rodgers found Tom Crabtree to make it 35-17. After a Texan interception, Rodgers found James Jones again to make it 42-17. Houston scored before the buzzer to have the final score 42-24.
Question: How many points was Houston trailing by at the half?
Answer: 11