Answer:
f(3) = 16 and f(4) = 23
Step-by-step explanation:
Finding f(3) simply means we're finding the value of the function when x = 3, so we can plug 3 in for x in our function:
f(3) [tex]3^{2} +7[/tex]
[tex]3^2 = 9[/tex], so now we have:
f(3) = 9 + 7
9 + 7 = 16, so f(3) = 16.
Now we want to find the value of x that makes the function equal 23, so let's set our function equal to 23:
[tex]23 = x^2 + 7[/tex]
We want to get x by itself in order to find the value, so let's start by subtracting 7 from both sides:
23 - 7 = [tex]x^2[/tex]
23 - 7 = 16, so 16 = [tex]x^2[/tex]
Now, we can take the square root of both sides:
[tex]\sqrt{16} = \sqrt{x^2} \\\sqrt{16} = 4\\\sqrt{x^2} = x[/tex], so now we have:
4 = x
