What is the range of f(x) = 3x + 9 given x > 0?
{y | y < 9}, {y | y > 9}, {y | y > 3}, {y | y < 3}

Solution:

The range of a function in algebra is the set of all its outputs.

Given:

function f(x) = 3x + 9 and the domain (value of x) of x is x > 0.

Let us substitute the value of x greater than 0 and observe the result.

f(x) = 3x + 9

Put x = 1

f(1) = 3(1) + 9

f(1) = 3 + 9 = 12

Put x = 2

f(2) = 3(2) + 9

f(2) = 6 + 9 = 15

The value of f(x) is increasing for every increasing value of x

Therefore the range will be y > 9

---

What is the range of f(x) = 3x + 9 given x > 0?

Summary:

The range of the function f(x) = 3x + 9 will be {y | y > 9}