Posted by Monique on Sunday, May 11, 2008 at 5:19pm.
For all real numbers, f(x)=(x^2+1)/2. If f(a)=25 and f(11)=b, what could be the value of ba?
I'm confused on how you do these problems. Can someone show me how to do them? Thanks much!

Math  bobpursley, Sunday, May 11, 2008 at 6:01pm
I will start you on b
f(11)=(11^2+1)/2=61 so b is 61
25=(a^2+1)/2 solve for a.... 
Math  Monique, Sunday, May 11, 2008 at 6:13pm
Ok, so f(25)=(25^2+1)/2. 626/2=313. So, a=313. When substituted, 61313 is 252.
There's a small issue though. This question is multiple, and I don't see a 252 as one of the choices:
a. 14
b. 36
c. 68
d. 77
e. 86
Did I do something wrong?