Answer :
We are given function f(x) = 3x+9.
We need to find the range of the given function.
We are given options
A) {y | y < 9}
B) {y | y > 9}
C) {y | y > 3}
D) {y | y < 3}
From the given options we can think that x is in the exponent of 3.
So, the given function is actually f(x) = 3^x +9
Now, we need to find the range of given function.
We can see that first term is and exponential term 3^x and second term is 9.
We know that 3^x will always be greater than 0.
Therefore, 3^x +9 would always be greater than 9.