Question #N453

The function $f(x) = x^2 - 4x + 3$ is graphed in the xy-plane. What is the y-coordinate of the y-intercept of the graph of $f(x)$?
A. 1
B. 3
C. -1
D. -3

Correct Answer is: B

The y-intercept of the graph of a function is the point where the graph crosses the y-axis. This occurs when $x=0$. Substituting 0 for $x$ in the equation $f(x) = x^2 - 4x + 3$ gives us $f(0) = 0^2 - 4(0) + 3$, or $f(0) = 3$. Therefore, the y-coordinate of the y-intercept of the graph of $f(x)$ is 3.