Explanation

A diameter divides a circle into two equal halves.

Any angle formed at the circumference by a diameter is 90°.

This is a key property of circles in geometry.

It is based on the angle in a semicircle theorem.

Always forms a right-angled triangle inside the circle.

Last verified on 25-05-2026

Explanation

• Area of triangle depends on base and height.
• Formula:
• If base doubles and height becomes half, the product remains unchanged.
• So, the area does not change.
• Final area remains the same.

Last verified on 25-05-2026

Explanation

A triangle with sides 5, 12, and 13 follows Pythagoras theorem.

5² + 12² = 25 + 144 = 169 = 13².

So, it forms a right-angled triangle.

It is a special Pythagorean triplet.

Right angle is opposite the longest side (13).

Last verified on 25-05-2026

Explanation

• A diameter is the longest chord of a circle.
• Angle subtended by a diameter at the circumference is always 180°.
• This forms a straight line at the circle’s edge.
• It is based on circle geometry principles.

Last verified on 24-05-2026

Explanation

secθ = 1/cosθ, so  

secθ × cosθ = (1/cosθ) × cosθ = 1

Last verified on 24-05-2026