Math 4 (Triangle & Quadrilaterals) | PDF - Free Printable

Problem Analysis:

The task involves understanding and applying concepts related to triangles and quadrilaterals. Let's solve each section step by step.

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Section I: Fill in the blanks with the correct words from below.

The given words are:
obtuse, equilateral, isosceles, acute, scalene, right, angles, triangle, sides

#### 1. It has a 90° angle.
- A triangle with a 90° angle is called a right triangle.
- Answer: right

#### 2. All of its angles are less than 90°.
- A triangle where all angles are less than 90° is called an acute triangle.
- Answer: acute

#### 3. It has an angle greater than 90°.
- A triangle with one angle greater than 90° is called an obtuse triangle.
- Answer: obtuse

#### 4. It has three equal angles, each having a measure of 60°.
- A triangle with three equal angles (each 60°) is called an equilateral triangle.
- Answer: equilateral

#### 5. It has two equal sides.
- A triangle with two equal sides is called an isosceles triangle.
- Answer: isosceles

#### 6. It has no equal sides.
- A triangle with no equal sides is called a scalene triangle.
- Answer: scalene

#### 7. All its three sides are equal.
- A triangle with all three sides equal is called an equilateral triangle.
- Answer: equilateral

#### 8. It is a three-sided figure.
- A three-sided figure is called a triangle.
- Answer: triangle

#### 9. Triangles are named according to the measures of their ________.
- Triangles are classified based on the measures of their angles.
- Answer: angles

#### 10. And according to the lengths of their ________.
- Triangles are also classified based on the lengths of their sides.
- Answer: sides

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Section II: Match the figure with the correct description.

#### Figure A:
- Description: "all its angles measure less than 90°"
- This describes an acute triangle.
- Answer: 4. acute triangle

#### Figure B:
- Description: "all its three sides are equal"
- This describes an equilateral triangle.
- Answer: 3. equilateral triangle

#### Figure C:
- Description: "it has no equal sides"
- This describes a scalene triangle.
- Answer: 1. scalene triangle

#### Figure D:
- Description: "all its three angles are equal and measure 60°"
- This describes an equilateral triangle.
- Answer: 5. equiangular triangle

#### Figure E:
- Description: "it has two equal sides"
- This describes an isosceles triangle.
- Answer: 2. isosceles triangle

#### Figure F:
- Description: "exactly two angles are 60°"
- This describes an isosceles triangle (since two angles being 60° implies the third angle is 60°, making it equilateral, but the context here suggests isosceles).
- Answer: 2. isosceles triangle

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Section III: Which word inside the box gives the name of the figures below?

The given words are: rhombus, kite, rectangle, parallelogram, square, trapezoid

#### 1. Square
- The figure is a square (all sides equal, all angles 90°).
- Answer: square

#### 2. Trapezoid
- The figure is a trapezoid (one pair of parallel sides).
- Answer: trapezoid

#### 3. Kite
- The figure is a kite (two pairs of adjacent equal sides).
- Answer: kite

#### 4. Parallelogram
- The figure is a parallelogram (opposite sides are parallel and equal).
- Answer: parallelogram

#### 5. Rectangle
- The figure is a rectangle (opposite sides are equal, all angles 90°).
- Answer: rectangle

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Section IV: Name the each figures. Mind the spelling.

#### 1.
- All sides are equal (5 cm), and one angle is 90°.
- Answer: Isosceles right triangle

#### 2.
- Two sides are equal (7 cm), and the base is 5 cm.
- Answer: Isosceles triangle

#### 3.
- All angles are less than 90°, and no sides are equal.
- Answer: Scalene acute triangle

#### 4.
- One angle is 90° (sum of other angles = 90°).
- Answer: Right triangle

#### 5.
- All angles are equal (60° each).
- Answer: Equilateral triangle

#### 6.
- One angle is 90°, and the other two angles are 30° and 60°.
- Answer: Right triangle

#### 7.
- All angles are equal (60° each).
- Answer: Equilateral triangle

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Final Answers:

Section I:
1. right
2. acute
3. obtuse
4. equilateral
5. isosceles
6. scalene
7. equilateral
8. triangle
9. angles
10. sides

Section II:
1. C
2. E
3. B
4. A
5. D

Section III:
1. square
2. trapezoid
3. kite
4. parallelogram
5. rectangle

Section IV:
1. Isosceles right triangle
2. Isosceles triangle
3. Scalene acute triangle
4. Right triangle
5. Equilateral triangle
6. Right triangle
7. Equilateral triangle

Boxed Final Answer:
\[
\boxed{
\text{See detailed answers above.}
}
\]