The correct value in this function is f(21) = 157
This question is related to substitution of values. To solve it, just: change x by the indicated value and thus calculate normally.
– The given function being f(x) = 8x - 11, replace X by 21:
f(x) = 8x - 11
f(21) = 8 . 21 - 11
– Finally, just calculate the expression now, like this, multiplying and subtracting the numbers:
f(21) = 8 . 21 - 11
f(21) = 168 - 11
f(21) = 157
Therefore, the correct value of this function will be f(21) = 157