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

Explanation

We use sin²θ + cos²θ = 1  

cos²θ = 1 - sin²θ  

cos²θ = 1 - (7/25)²  

cos²θ = 1 - 49/625  

cos²θ = 576/625  

cosθ = ±√(576/625) = ±24/25

Sign depends on the quadrant of θ

Last verified on 24-05-2026

Explanation

If base = b, height = h, then area = b × h. 

New base = b × 1.20 = 1.2b  

New height = h × 0.80 = 0.8h  

New area = 1.2b × 0.8h = 0.96bh = 0.96 × original area

Last verified on 24-05-2026

Explanation

• A triangle with all angles equal is an equilateral triangle.
• Each angle in this triangle is 60°.
• All sides are also equal in length.
• It is a regular and perfectly symmetrical triangle.

Last verified on 24-05-2026