20. Given f(x) = 2x + 9, if f(x) = 15, find x.

The value of x if f(x) = 15 in the given function is 3

From the question,

We were given the function f(x) = 2x + 9

To determine the value of x if f(x) = 15, we will put f(x) to be equals to 15 and then solve for x in the equation

That is,

f(x) = 2x + 9

Since f(x) = 15

∴ 15 = 2x + 9

Now, to solve the above equation,

First, subtract 9 from both sides

That is,

15 - 9 = 2x +9 -9

6 = 2x

Then, we can write that

2x = 6

∴ x = 6 ÷ 2

x = 3

Hence, the value of x if f(x) = 15 in the given function is 3

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the answer is located in the screenshot that is attached.

Step-by-step explanation:

The work is also in the screenshot attached. Hoped this helped!

answer: 1, 3 and 5 are correct

step-by-step explanation: