Graph each piece with its domain in braces. Click the x-value the item asked for on the piece that owns that x. Desmos access is in Desmos on the ACT.
One line per piece
y = x + 1{x < 0} and y = 2x{x ≥ 0} are two entries, not one. Domain braces are in domain restrictions. After you have a value, check it, in checking your work.
Evaluating a single function at a point is in evaluating a function at a point.
The bottom line
Each piece, its inequality, its graph. Read from the piece that includes that x.
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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