Questions: If f(x)=x^2-4x, find f(a) f(a)= (Simplify your answer. Do not factor.)

Solution Steps

To find \( f(a) \) for the given function \( f(x) = x^2 - 4x \), we need to substitute \( a \) for \( x \) in the function and simplify the expression.

1. Substitute \( a \) for \( x \) in the function \( f(x) = x^2 - 4x \).
2. Simplify the resulting expression to find \( f(a) \).

We start with the function \( f(x) = x^2 - 4x \). To find \( f(a) \), we substitute \( a \) for \( x \): \[ f(a) = a^2 - 4a \]

Next, we evaluate \( f(a) \) by substituting \( a = 5 \): \[ f(5) = 5^2 - 4 \cdot 5 \]

Now, we simplify the expression: \[ f(5) = 25 - 20 = 5 \]

Final Answer