Given f, left bracket, x, right bracket, equals, minus, x, squared, plus, 9, x, minus, 17f(x)=−x
2
+9x−17, find f, left bracket, minus, 5, right bracketf(−5)
To find f(-5), we substitute -5 for x in the expression for f(x).
f(x) = -x^2 + 9x - 17
f(-5) = -(-5)^2 + 9(-5) - 17
Simplifying,
f(-5) = -25 - 45 - 17
f(-5) = -87
To find f(-5), we need to substitute -5 into the function f(x) and simplify the expression.
First, let's substitute -5 for x in the function f(x):
f(-5) = -(-5)^2 + 9(-5) - 17
Next, we'll simplify the expression:
f(-5) = -(25) + (-45) - 17
Now, perform the multiplications and additions:
f(-5) = -25 - 45 - 17
Finally, add the terms together to get the final result:
f(-5) = -87
To find the value of f(-5), we need to substitute -5 into the given equation for x.
The given equation is f(x) = -x^2 + 9x - 17.
To find f(-5), we substitute -5 for x in the equation:
f(-5) = -(-5)^2 + 9(-5) - 17
Simplifying this expression step by step:
= -(25) + (-45) - 17 (since -5 squared is 25)
= -25 - 45 - 17
= -70 - 17
= -87
Therefore, f(-5) = -87.