Ok, we can go one by one to solve these problems.
Hoever, let's note that if we have f(x) = x, then we set the right side of the function to equal x.
Then, we see if the x value satisfies the conditions given.
First, we have \(f(x) = 2x + 8\). Setting this to equal x, we fuind that \(x=2x+8\)
Solving for x, we find that \(x=-8\). This doesn't satisfy the condition \(1 \le x \le 2\), so it is not a valid solution.
Next, we have \(f(x) = 13 - 5x\). Setting this to equal x, we have \(x=13-5x\)
Finding the value of x, we get \(x=13/6\). This satisfies the inerval, so it is a solution.
Third, we have \(f(x) = 20 - 14x\). Since this equals x, we can write \(x = 20 - 14x\)
Trying to find x, we have that \(x=20/15=4/3\). This does NOT satisfy the interval, so it is not a solution.
Lastly, we have \(f(x) = 40 + 5x \). setting this function to equal x, we have \(x=40+5x\)
Solving for x, we get \(x=-10\), which is invalid.
Thus, the only value that works i 13/6.
So our answer is 13/6.
Thanks! :)