2-D shapes (age 10+) · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.

Drawing shapes to exact measurements

Mathematics · Geometry · ages 10-11
Name ______________________   Date ____________

  1. A rectangle measures 6 cm by 5 cm. What is its area in square centimetres?

    Answer: ______________

  2. A rectangle is 7 cm long and 4 cm wide. What is its perimeter in centimetres?

    • 11
    • 28
    • 18
    • 22

  3. Which two tools do you need to draw a shape accurately from given side lengths and angles?

    • A ruler and a protractor
    • A calculator and a compass
    • A ruler only

  4. A rectangle can be drawn accurately using only a ruler, with no need to check the angles.

    Circle one:   True   False

  5. Two angles of a triangle are 60 degrees and 70 degrees. How many degrees is the third angle?

    Answer: ______________

  6. A regular pentagon has a side length of 4 cm and an interior angle of 108°. What should you check with your protractor at each corner as you draw it?

    • That the angle measures 108°
    • That the angle measures 90°
    • That the angle measures 60°

  7. What is the interior angle of a regular pentagon in degrees?

    • 108
    • 120
    • 90
    • 100

  8. Mia draws a rectangle 5 cm by 3 cm and says its area is 8 square centimetres because 5 + 3 = 8. Is Mia right?

    Circle one:   True   False

  9. Marcus drew a triangle with a 5 cm side and a 7 cm side, and used his protractor to mark 60°, but he read the wrong scale on the protractor. What is most likely wrong with his triangle?

    • The two side lengths got swapped
    • The angle between the two sides probably is not really 60°
    • The triangle will end up with a right angle instead

  10. A triangle has two sides 5 cm and 7 cm long. The angle between them is 60 degrees. What type of triangle must it be?

    • Equilateral
    • Isosceles
    • Scalene
    • Right-angled
LightMySky · lightmysky.comW1-mt_hdrMoiTgqu-s1

Answer key

For grown-ups. Fold this page away before handing over the rest.

Drawing shapes to exact measurements W1-mt_hdrMoiTgqu-s1

  1. 30 · The area is 30 square centimetres because length times width is 6 times 5.
  2. 22 · The perimeter is 22 cm because opposite sides match: 7 + 4 + 7 + 4 = 22.
  3. A ruler and a protractor · The ruler measures the sides and the protractor measures the angles.
  4. False · Every corner of a rectangle must be exactly 90°, so you need a set square or protractor to check that.
  5. 50 · The third angle is 50 degrees because the three angles of a triangle total 180.
  6. That the angle measures 108° · Every interior angle in this regular pentagon is 108°, so your protractor should confirm that at each corner.
  7. 108 · 108 degrees is correct because the interior angles of a pentagon total 540 degrees, and 540 divided by 5 is 108.
  8. False · Mia is wrong. Area multiplies the sides: 5 times 3 = 15 square centimetres, not 8.
  9. The angle between the two sides probably is not really 60° · Protractors have two scales, so reading the wrong one is a common way to get the wrong angle, like 120° instead of 60°, even when both sides are the correct length.
  10. Scalene · Scalene is correct because the three sides work out to 5 cm, 7 cm and about 6.2 cm, all different.
Worksheet · LightMySky