SOLUTION: Im taking the act test on tuesday and I know if I can just see how this problem is solved I could figure out the other ones. Please help! Let f(x)= 4x - 3 if f(a) = 9 and f(b) = 5

Algebra ->  Functions -> SOLUTION: Im taking the act test on tuesday and I know if I can just see how this problem is solved I could figure out the other ones. Please help! Let f(x)= 4x - 3 if f(a) = 9 and f(b) = 5       Log On


   

Question 766867: Im taking the act test on tuesday and I know if I can just see how this problem is solved I could figure out the other ones. Please help! Let f(x)= 4x - 3 if f(a) = 9 and f(b) = 5 then what is f(a+b)?
Thanks!
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
Just follow the definition of the function for each given variable value.

f(a)=9=4(a)-3
9=4a-3
6=4a
a=3/2

f(b)=4*b-3=5 as given and according to function...
and find b...

What you do next? The same function...!