Triangle similarity: AA, SSS and SAS

Answer Key - Grade 10 Math Worksheet - Building Confidence

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

1. 1.

   Jun compares two tent doors, △CDF and △QSU. Which rule proves △CDF ~ △QSU?

   • Not enough to tell
   • AA
   • SAS~
   • SSS~
2. 2.

   Kira compares two kite halves, △CDF and △QSU. Which rule proves △CDF ~ △QSU?

   • Not enough to tell
   • SSS~
   • SAS~
   • AA
3. 3.

   Luz compares two sails, △CDF and △QSU. Which rule proves △CDF ~ △QSU?

   • SAS~
   • AA
   • SSS~
   • Not enough to tell
4. 4.

   Milo compares two roof fronts, △CDF and △QSU. Which rule proves △CDF ~ △QSU?

   • SAS~
   • Not enough to tell
   • AA
   • SSS~

5. Read this first

   Ratio table

   Columns small triangle | large triangle; rows shortest 4 | 8, middle 6 | 12, longest 7 | ?. Lengths in cm.

6. 5.

   Noah checks two triangle tiles and wants them similar by SSS~. The table pairs the sides by size. How long must the longest side of the large triangle be, in cm?

   14

7. Ratio table

   Columns small triangle | large triangle; rows shortest 6 | 10, middle 9 | 15, longest 10 | ?. Lengths in cm.

8. 6.

   Pia cuts two paper triangles for a mobile and wants them similar by SSS~. The table pairs the sides by size. How long must the longest side of the large triangle be, in cm?

   50/3

9. Ratio table

   Columns small triangle | large triangle; rows shortest 8 | 10, middle 12 | 15, longest 14 | ?. Lengths in cm.

10. 7.

    Tala measures two triangle window panes and wants them similar by SSS~. The table pairs the sides by size. How long must the longest side of the large triangle be, in cm?

    35/2
11. 8.

    Ari opens a pair of scissors. CG and DF cross at Y, CD ∥ GF, and △YCD ~ △YGF by AA. How long is YG, in cm?

    15
12. 9.

    Bo looks at a folding table from the side. CG and DF cross at Y, CD ∥ GF, and △YCD ~ △YGF by AA. How long is YG, in cm?

    12
13. 10.

    Esme maps two parallel streets crossed by two roads. CG and DF cross at Y, CD ∥ GF, and △YCD ~ △YGF by AA. How long is YG, in cm?

    15