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GRE Math: Angles And Triangles

Instructions:

Answer 37 questions in 15 minutes.
If you are not ready to take this test, you can study here.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. congruent angles
90
S^2*sqrt(3)/4
Equal
Two angles totalling 90

2. 3-4-?
5
All equal sides
SAS SSS ASA SAA HL
More than 90 but less than 180

3. 10-24-?
20
26
The base may be equal - greater or less than any other side - the legs are equal - angle across base is the vertex angle (+><) - base angles are equal
SAS SSS ASA SAA HL

4. vertical angles
Opposite angles formed when two lines cross
15
8
SAS SSS ASA SAA HL

5. exterior angle
C2=a2+b2
13
3 unequal sides
Extend one side of the triangle

6. 6-8-?
All equal sides
8
The sum of any two sides muse be greater than the 3rd side - the largest side lies opposite the largest angle and vice versa
61

7. 5-12-?
15
At least 2 equal sides
13
The base may be equal - greater or less than any other side - the legs are equal - angle across base is the vertex angle (+><) - base angles are equal

8. area of triangle
5
3 unequal sides
.5B*h
SAS SSS AAA

9. 11-60-?
Angles less than 90/between 90 and 180
61
More than 180
180

10. acute/obtuse triangle
Angles less than 90/between 90 and 180
25
A line that bisects (halves) an angle in a triangle
61

11. 15-20-?
S^2*sqrt(3)/4
25
Line segment from a vertex perpendicular to the base
A line that bisects (halves) an angle in a triangle

12. median
Line drawn from any angle of a triangle to the midpoint of the opposite side
180
More than 180
A line that bisects (halves) an angle in a triangle

13. scalene triangle
20
The sum of any two sides muse be greater than the 3rd side - the largest side lies opposite the largest angle and vice versa
3 unequal sides
90

14. congruent triangles
Two angles totalling 180
SAS SSS ASA SAA HL
.5B*h
All equal sides

15. 30-60-90 right triangle
17
The base may be equal - greater or less than any other side - the legs are equal - angle across base is the vertex angle (+><) - base angles are equal
Get shorter leg first - shorter leg is half hyp - to find short leg given hyp - div by 2 - to find hyp given short leg - *2 - find short leg given hyp - div by sqrt3 - find long leg given short leg - *sqrt3
8

16. reflex angle
61
More than 180
Two angles totalling 180
26

17. altitute/height
Get shorter leg first - shorter leg is half hyp - to find short leg given hyp - div by 2 - to find hyp given short leg - *2 - find short leg given hyp - div by sqrt3 - find long leg given short leg - *sqrt3
SAS SSS ASA SAA HL
Line segment from a vertex perpendicular to the base
All equal sides

18. Following is true about isosceles triangles
The sum of any two sides muse be greater than the 3rd side - the largest side lies opposite the largest angle and vice versa
The base may be equal - greater or less than any other side - the legs are equal - angle across base is the vertex angle (+><) - base angles are equal
Less than 90
Line segment from a vertex perpendicular to the base

19. 7-24-?
17
3 unequal sides
25
The base may be equal - greater or less than any other side - the legs are equal - angle across base is the vertex angle (+><) - base angles are equal

20. acute angle
25
Less than 90
Angles less than 90/between 90 and 180
All equal sides

21. 9-12-?
15
26
180
17

22. 9-40-?
41
.5B*h
Extend one side of the triangle
25

23. 20-21-?
17
All equal sides
3 unequal sides
29

24. pythagorean theorem
Less than 90
C2=a2+b2
The sum of any two sides muse be greater than the 3rd side - the largest side lies opposite the largest angle and vice versa
13

25. complementary angles
Two angles totalling 90
Opposite angles formed when two lines cross
41
S^2*sqrt(3)/4

26. 8-15-?
13
180
Less than 90
17

27. area of equilateral triangle
The base may be equal - greater or less than any other side - the legs are equal - angle across base is the vertex angle (+><) - base angles are equal
S^2*sqrt(3)/4
90
More than 90 but less than 180

28. 2 facts about triangles
Two angles totalling 180
SAS SSS ASA SAA HL
The sum of any two sides muse be greater than the 3rd side - the largest side lies opposite the largest angle and vice versa
26

29. supplementary angles
Two angles totalling 90
SAS SSS ASA SAA HL
Two angles totalling 180
At least 2 equal sides

30. angle bisector
25
3 unequal sides
A line that bisects (halves) an angle in a triangle
17

31. straight angle
180
Opposite angles formed when two lines cross
3 unequal sides
15

32. 12-16-?
Equal
20
Less than 90
All equal sides

33. equilateral triangle
All equal sides
C2=a2+b2
The sum of any two sides muse be greater than the 3rd side - the largest side lies opposite the largest angle and vice versa
Get shorter leg first - shorter leg is half hyp - to find short leg given hyp - div by 2 - to find hyp given short leg - *2 - find short leg given hyp - div by sqrt3 - find long leg given short leg - *sqrt3

34. similar triangles
20
SAS SSS AAA
SAS SSS ASA SAA HL
At least 2 equal sides

35. obtuse angle
3 unequal sides
180
.5B*h
More than 90 but less than 180

36. isosceles triangle
At least 2 equal sides
13
90
5

37. right angle
5
The sum of any two sides muse be greater than the 3rd side - the largest side lies opposite the largest angle and vice versa
90
Get shorter leg first - shorter leg is half hyp - to find short leg given hyp - div by 2 - to find hyp given short leg - *2 - find short leg given hyp - div by sqrt3 - find long leg given short leg - *sqrt3