Triangle/Angle Vocabulary
A triangle with all acute angles is called...
an acute triangle
An even number...
can always be divided by 2
The amount of degrees in a right angle
90 degrees
This type of triangle has sides that are all the same length.
Equilateral
2, 3, 5, 7
all the prime numbers under ten
A triangle with two angles greater than 90 degrees is called...
an obtuse triangle
A prime number's factors are always 1 and what?
itself
An acute angle measures...
less than 90 degrees
This type of triangle has no sides that are the same length.
Scalene
True or false: all even numbers are composite.
True! All even numbers can be divided evenly by 2 making them composite.
90 degrees
3 factors
What's the missing angle if a right triangle has another angle measuring 45 degrees?
45 degrees
If a triangle has a two sides that are marked with 2 hashes and one side with only 1 hash mark that makes it what type of triangle?
Isoceles
True or false: all odd numbers are composite. Why or why not?
False! 9 is odd, but can be divided by 3, for example.
This angle measures 180 degrees
Straight angle
What is a tool that you must always use to figure out prime and composite numbers?
a divisibility chart
This triangle has two angles measuring 70 degrees and 30 degrees. What's the missing angle?
80 degrees
An isoceles triangle's sides add up to 18. If one side is 10 units, how many units are the other 2?
4 units each
Which one is prime? 27, 45, 51
51
27 can be divided by 3 (3x9)
45 can be divided by 5 (5x9)
180 degrees
This number is neither prime nor composite
1
The angle measurement in an equilateral triangle
60 degrees (180 divided by 3 angles = 60)
Draw a scalene triangle with measurements on each side.
Teacher decides!
Complete the entire divisibility chart for 35, 42, 86, 29
Teacher decides!