16Hit1600
Geometry and TrigonometryHardLeg of an isosceles right triangle from its hypotenuse

Geometry and Trigonometry practice question

A square napkin is folded along a diagonal to make a right triangle whose longest side is 12 centimetres. What is the length, in centimetres, of each of the other two sides? Round to the nearest tenth.

Answer: 8.5

The triangle is isosceles and right, so each leg is 12/√2 = 6√2 ≈ 8.5.

Common wrong answers

If you answered 6
6 halves the hypotenuse; the legs are longer than half of it.
If you answered 17
17 is 12√2, multiplying instead of dividing.
If you answered 8.7
8.7 is 12 × (√3/2), using 60° ratios instead of 45°.

More Geometry and Trigonometry questions

Not affiliated with the College Board. SAT is a trademark of the College Board.