Question

1. f(x) = x² + 10x + 20; find f(-3)

Explanation:

Step1: Substitute \( x = -3 \) into the function

Substitute \( x = -3 \) into \( f(x) = x^2 + 10x + 20 \), we get \( f(-3)=(-3)^2 + 10\times(-3)+20 \).

Step2: Calculate each term

First, calculate \( (-3)^2 = 9 \), \( 10\times(-3)= -30 \). Then substitute these values back: \( f(-3)=9 - 30 + 20 \).

Step3: Simplify the expression

Simplify \( 9 - 30 + 20 \), we have \( 9 + (-30 + 20)=9 - 10=-1 \).

Answer:

\( f(-3)=-1 \)