Chapter 5 · Class 10 ICSE · Formula Sheet
Circles (Tangents & Secants) Formulas — Class 10 ICSE
Study tangent properties, alternate segment theorem, and intersecting chords.
Key Formulas
Tangent-Radius
\text{Tangent} \perp \text{Radius}
Tangent Lengths
PA = PB \text{ (from external point)}
Alternate Segment
\text{Angle between tangent and chord} = \text{Angle in alternate segment}
Intersecting Chords
PA \times PB = PC \times PD
Tangent-Secant
PT^2 = PA \times PB
Worked Examples
1Using: Area of Circle
Find the area of a circle with radius 7 cm.
Step 1: Area = pi x r^2
Step 2: = 22/7 x 49 = 154 sq. cm.
Answer: 154 sq. cm
2Using: Circumference
Find the circumference of a circle with radius 14 cm.
Step 1: C = 2 x pi x r
Step 2: = 2 x 22/7 x 14 = 88 cm.
Answer: 88 cm
Practice Now
Apply these formulas with 60+ practice questions and AI-powered doubt clearing.
More Class 10 ICSE Formulas
Frequently Asked Questions
How many formulas are in Class 10 ICSE Circles (Tangents & Secants)?+
How to remember Circles (Tangents & Secants) formulas easily?+
Are these Circles (Tangents & Secants) formulas enough for exams?+
Master Circles (Tangents & Secants) on SparkEd
Go beyond formulas. Practice at three difficulty levels with instant feedback, step-by-step solutions, and an AI coach.
Start Practising FreeSparkEd Maths provides free formula sheets for Class 1-10 across 7 education boards. All formulas are aligned to the 2025-26 syllabus.