DDesmos SAT Prep
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Linear–Quadratic Systems

Find where a line meets a parabola — 0, 1, or 2 points.

The Desmos trick

Graph the line and the parabola together. Click each intersection point. If the line just grazes the curve (tangent), there's exactly one point — Desmos shows it clearly even when the algebra (discriminant = 0) is easy to miss.

  • Graph both expressions on separate lines in the same calculator
  • Click every visible intersection — don't assume there's only one
  • If you see no crossing, zoom out before concluding there's no solution