Graph the function and click where it meets the x-axis. Those points are the roots. y = 0 is the same click. Desmos access is in Desmos on the ACT.
Crossings on the axis
A quadratic can have two, one, or none. No crossing means no real roots, which is also what a negative discriminant says, in the discriminant. The vertex is a different click, in finding a vertex.
Two curves crossing each other are intersections, in finding intersections.
The bottom line
X-intercepts are the x-axis clicks. Do not confuse them with a vertex.
Start practicing
Start with a free diagnostic, then drill your weak spots with 15-question quizzes and track how you're doing across Reading, English, and Math. Compare plans whenever you're ready to go further.
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