Digital SATMath: Geometry and TrigonometryEasy

A construction worker is installing a new window. The window frame is perfectly rectangular, and its diagonal measures 5 feet. If the height of the window is 3 feet, what is the width of the window?

  1. A2 feet
  2. B4 feet
  3. C8 feet
  4. D6 feet
Show answer & explanation

Correct answer: B. 4 feet

The window frame forms a right-angled triangle with its height, width, and diagonal. Using the Pythagorean theorem (a^2 + b^2 = c^2), where c is the diagonal, we can find the width.

Why the other options are wrong

  • A. Incorrect. This would imply a shorter diagonal (sqrt(3^2+2^2) = sqrt(13) approx 3.6 feet).
  • C. Incorrect. This would imply a much longer diagonal (sqrt(3^2+8^2) = sqrt(73) approx 8.5 feet).
  • D. Incorrect. This would imply a longer diagonal (sqrt(3^2+6^2) = sqrt(45) approx 6.7 feet).

Pythagorean Theorem Application

The Pythagorean theorem (a^2 + b^2 = c^2) is used to find an unknown side of a right-angled triangle when two sides are known.

  • Applies only to right-angled triangles.
  • c always represents the hypotenuse (the longest side, opposite the right angle).
  • a and b represent the other two sides (legs).

Memory trick: Right angle, right answer, sides squared, sum it up!

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