# How do you find the y-intercept of y = x^2 - 4x + 4?

Dec 16, 2015

y-intercept$=$4

#### Explanation:

Since any y-intercept has an x-coordinate of $0$, substitute $0$ as your $x$ value into the equation and solve for $y$:

$y = {x}^{2} - 4 x + 4$
$y = {\left(0\right)}^{2} - 4 \left(0\right) + 4$
$y = 0 - 0 + 4$
$y = 4$

A quicker approach would be to look at the $c$ value of the equation, which is also the y-intercept. Recall that the standard form of a quadratic equation is written like:

$y = a {x}^{2} + b x + c$

Thus, by looking at the equation, you can tell that the y-intercept is $4$.