Question

what is the value of f(-3) for each function?

1. f(x) = 4x - 9
2. f(x) = \frac{1}{3}x + 13
3. f(x) = -2x - 11

Explanation:

Step1: Solve for \( f(-3) \) in \( f(x) = 4x - 9 \)

Substitute \( x = -3 \) into the function: \( f(-3)=4(-3)-9 \)
Calculate: \( 4(-3)= -12 \), then \( -12 - 9 = -21 \)

Step2: Solve for \( f(-3) \) in \( f(x)=-\frac{1}{3}x + 13 \)

Substitute \( x = -3 \) into the function: \( f(-3)=-\frac{1}{3}(-3)+13 \)
Calculate: \( -\frac{1}{3}(-3)=1 \), then \( 1 + 13 = 14 \)

Step3: Solve for \( f(-3) \) in \( f(x)=-2x - 11 \)

Substitute \( x = -3 \) into the function: \( f(-3)=-2(-3)-11 \)
Calculate: \( -2(-3)=6 \), then \( 6 - 11 = -5 \)

Answer:

1. \( f(-3) = -21 \)
2. \( f(-3) = 14 \)
3. \( f(-3) = -5 \)