ACT Preparation / Unit 10 ACT 0921 short lesson, about 20 seconds
The Absolute Value Function
Captions available
The idea
The absolute value function, f(x) = |x|, makes a V with its vertex at the origin. In y = a|x − h| + k, the vertex moves to (h, k).
In practice
y = |x + 1| − 2 has its vertex at (−1, −2) and opens up.
Where people slip
A negative a turns the V upside down, and its vertex becomes a maximum.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Something wrong in this lesson? Flag it · Sources for ACT Preparation