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Find the distance from P to the plane.

Read the idea, work independently, then explain what changed.

TOPIC 01

Space vectors and solid geometry: mixed review

A mixed assessment: identify the method, justify it and revise your reasoning.

What you will be able to explain

  • Connect the chapter skills without relying on the order of the exercises.

Try it. Leave your reasoning visible.

Use one hint at a time. A correction explains what changed, not just the final answer.

01 / Standard#Your turn

Find the distance from P to the plane.

P=(27,0,0),Π:3x+4y=0P=(27,0,0),\quad \Pi:3x+4y=0
  • Use acute line/plane angles; normals must be nonzero and distances nonnegative.
Skills and prerequisite lessons

Working and explanation

BUILD THE REASONING

Hint 1
Use the dot product to connect coordinates with length or angle.
Hint 2
Use this intermediate relation.
d=∣3xP+4yP∣/5d=|3x_P+4y_P|/5
Worked solution
  1. Use the dot product to connect coordinates with length or angle.

  2. Apply the stated relation and retain its conditions.

    d=3(27)/32+42=16.2d=3(27)/\sqrt{3^2+4^2}=16.2
  3. Normalize the plane normal; raw substitution is not a distance.

The requested value is 16.2.

Checks and common pitfalls: Normalize the plane normal; raw substitution is not a distance.

Think first. Reveal a hint when the class is ready.

Focus on one question

Teacher preparation and assessment

Question sequence

  • Ask students to name the relevant condition before calculating.

Board plan

  • Compare valid methods and annotate their conditions.

Anticipated thinking

  • A correct final value may still hide a missing assumption.

Assessment checklist

  • Check the method, conditions, reasoning and interpretation separately.

No sign-in. Work stays in this browser. Export before clearing browser data. Written reasoning is assessed with a checklist.

Curriculum and source notes ↗