Is it a right triangle? (the converse)

Answer Key - Grade 8 Math Worksheet - Building Confidence

Circle the best answer, or write your answer on the line.

1. 1.

   Bo cuts a paper triangle with sides of 9, 4 and 8 cm. What do the squares on the two shorter sides add up to, in square cm?

   80
2. 2.

   Jun draws a triangle with sides of 7, 9 and 5 cm on a poster. What do the squares on the two shorter sides add up to, in square cm?

   74
3. 3.

   Kira's class ropes off a triangle-shaped flower bed with sides of 11, 7 and 8 feet. What do the squares on the two shorter sides add up to, in square feet?

   113
4. 4.

   Luz's robot draws a triangle with sides of 40, 50 and 30 cm, then beeps twice. What do the squares on the two shorter sides add up to, in square cm?

   2500
5. 5.

   Milo glues three paper squares onto the sides of a triangle. Their areas are 20, 45 and 65 square cm. Is the triangle a right triangle?

   • You cannot tell without measuring the angles.
   • It is not a right triangle: the two smaller squares do not add up to the biggest one.
   • It is a right triangle, because one square is much bigger than the other two.
   • It is a right triangle: the two smaller squares add up to the biggest one.
6. 6.

   Noah's quilt has three square patches on the sides of a triangle, 50, 85 and 30 square inches. Is the triangle a right triangle?

   • It is not a right triangle: the two smaller squares do not add up to the biggest one.
   • It is a right triangle, because one square is much bigger than the other two.
   • It is a right triangle: the two smaller squares add up to the biggest one.
   • You cannot tell without measuring the angles.
7. 7.

   Pia builds squares of tiles on the sides of a triangle: 64, 24 and 40 square inches. Is the triangle a right triangle?

   • You cannot tell without measuring the angles.
   • It is a right triangle: the two smaller squares add up to the biggest one.
   • It is a right triangle, because one square is much bigger than the other two.
   • It is not a right triangle: the two smaller squares do not add up to the biggest one.
8. 8.

   Tala lists the sides of a triangle as 9, 4 and 7 cm. To test for a right angle, which square must the other two add up to?

   • The square on the side of 4 cm
   • The square on the side of 7 cm
   • The square on the side of 9 cm
9. 9.

   Zee's worksheet gives a triangle's sides as 12, 15 and 10 inches. To test for a right angle, which square must the other two add up to?

   • The square on the side of 10 inches
   • The square on the side of 15 inches
   • The square on the side of 12 inches
10. 10.

    Bo cuts a triangle with sides of 18, 13 and 8 cm. To test for a right angle, which square must the other two add up to?

    • The square on the side of 13 cm
    • The square on the side of 8 cm
    • The square on the side of 18 cm