Test your basic knowledge |

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. 9-12-?
17
Line drawn from any angle of a triangle to the midpoint of the opposite side
25
15

2. 7-24-?
Opposite angles formed when two lines cross
25
Extend one side of the triangle
More than 90 but less than 180

3. 20-21-?
Two angles totalling 180
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
29
.5B*h

4. similar triangles
Line segment from a vertex perpendicular to the base
3 unequal sides
SAS SSS AAA
5

5. area of equilateral triangle
26
3 unequal sides
S^2*sqrt(3)/4
Less than 90

6. 9-40-?
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
More than 180
41

7. straight angle
SAS SSS ASA SAA HL
Line drawn from any angle of a triangle to the midpoint of the opposite side
61
180

8. reflex angle
More than 180
Opposite angles formed when two lines cross
20
29

9. angle bisector
A line that bisects (halves) an angle in a triangle
29
Two angles totalling 90
S^2*sqrt(3)/4

10. 30-60-90 right triangle
SAS SSS ASA SAA HL
Less than 90
61
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

11. equilateral triangle
All equal sides
Line drawn from any angle of a triangle to the midpoint of the opposite side
Line segment from a vertex perpendicular to the base
Extend one side of the triangle

12. congruent triangles
SAS SSS ASA SAA HL
More than 90 but less than 180
26
Equal

13. 5-12-?
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
13
SAS SSS AAA

14. acute angle
20
Angles less than 90/between 90 and 180
Less than 90
S^2*sqrt(3)/4

15. supplementary angles
41
Line drawn from any angle of a triangle to the midpoint of the opposite side
Two angles totalling 180
The sum of any two sides muse be greater than the 3rd side - the largest side lies opposite the largest angle and vice versa

16. 3-4-?
5
25
Opposite angles formed when two lines cross
8

17. 6-8-?
8
Line drawn from any angle of a triangle to the midpoint of the opposite side
Opposite angles formed when two lines cross
15

18. 2 facts about triangles
25
Angles less than 90/between 90 and 180
Opposite angles formed when two lines cross
The sum of any two sides muse be greater than the 3rd side - the largest side lies opposite the largest angle and vice versa

19. 12-16-?
20
All equal sides
More than 90 but less than 180
41

20. Following is true about isosceles triangles
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
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
Equal

21. pythagorean theorem
90
C2=a2+b2
3 unequal sides
A line that bisects (halves) an angle in a triangle

22. complementary angles
Two angles totalling 90
25
8
S^2*sqrt(3)/4

23. acute/obtuse triangle
29
Angles less than 90/between 90 and 180
SAS SSS AAA
180

24. 10-24-?
S^2*sqrt(3)/4
26
15
61

25. exterior angle
.5B*h
Extend one side of the triangle
20
All equal sides

26. congruent angles
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
All equal sides
Equal
5

27. area of triangle
15
S^2*sqrt(3)/4
SAS SSS AAA
.5B*h

28. 11-60-?
41
180
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
61

29. vertical angles
Two angles totalling 90
29
180
Opposite angles formed when two lines cross

30. 15-20-?
Two angles totalling 180
8
25
29

31. altitute/height
All equal sides
3 unequal sides
180
Line segment from a vertex perpendicular to the base

32. right angle
90
41
13
17

33. isosceles triangle
At least 2 equal sides
Two angles totalling 180
41
15

34. median
Two angles totalling 180
Line drawn from any angle of a triangle to the midpoint of the opposite side
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
The sum of any two sides muse be greater than the 3rd side - the largest side lies opposite the largest angle and vice versa

35. scalene triangle
Line drawn from any angle of a triangle to the midpoint of the opposite side
61
S^2*sqrt(3)/4
3 unequal sides

36. obtuse angle
15
More than 90 but less than 180
41
A line that bisects (halves) an angle in a triangle

37. 8-15-?
17
8
180
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