Let's solve the problem step by step by filling in the blanks in the triangle classification chart. This is a common geometry topic that helps students understand how triangles are categorized based on their
angles and
sides.
---
🔷 Top Section:
>
Triangles
> Figure with 3 sides and 3 angles. Classified by
__________ and
__________
✔ Answer:
Triangles are classified by
angles and
sides.
So, fill in:
-
angles and
sides
---
🔷 Classifying by Angles
#### 1.
ACUTE
> All angles are acute
> (less than ___ degrees)
✔ Acute angles are less than
90 degrees.
So, fill in:
90
#### 2.
RIGHT
> One right angle
> (equal to ___ degrees)
✔ A right angle is exactly
90 degrees.
So, fill in:
90
#### 3.
OBTUSE
> One obtuse angle
> (greater than ___ degrees)
✔ An obtuse angle is greater than
90 degrees but less than 180.
So, fill in:
90
---
🔷 Classifying by Sides
#### 1.
EQUILATERAL
> All sides are the ________ length
✔ All three sides are equal.
So, fill in:
same
#### 2.
ISOSCELES
> _______ sides are the same length
✔ Two sides are equal.
So, fill in:
Two
#### 3.
SCALENE
> All sides are _______ lengths
✔ No sides are equal — all are different.
So, fill in:
different
---
✔ Final Completed Chart:
>
Triangles
> Figure with 3 sides and 3 angles. Classified by
angles and
sides
---
####
Classifying by Angles
-
ACUTE: All angles are acute (less than
90 degrees)
-
RIGHT: One right angle (equal to
90 degrees)
-
OBTUSE: One obtuse angle (greater than
90 degrees)
---
####
Classifying by Sides
-
EQUILATERAL: All sides are the
same length
-
ISOSCELES:
Two sides are the same length
-
SCALENE: All sides are
different lengths
---
📝 Summary of Answers:
| Blank | Answer |
|------|--------|
| Classified by ___ and ___ |
angles,
sides |
| Acute: less than ___ degrees |
90 |
| Right: equal to ___ degrees |
90 |
| Obtuse: greater than ___ degrees |
90 |
| Equilateral: all sides are the ___ length |
same |
| Isosceles: ___ sides are the same length |
Two |
| Scalene: all sides are ___ lengths |
different |
This completes the worksheet! It teaches the two main ways to classify triangles: by their
angle measures and by their
side lengths.
Parent Tip: Review the logic above to help your child master the concept of classifying triangles by sides and angles worksheet answers.
