Chapter 7 · Class 8 ICSE · Formula Sheet

Linear Equations in One Variable Formulas — Class 8 ICSE

Solve linear equations with variables on both sides and apply to practical problems.

Key Formulas

Standard Form

ax + b = 0

Solution

x = -\dfrac{b}{a}

Cross Multiplication

\dfrac{a}{b} = \dfrac{c}{d} \implies ad = bc

Worked Examples

1Using: Supplementary Angles

If one angle is 65 degrees, find its supplement.

Step 1: Supplement = 180 - 65

Step 2: = 115 degrees.

Answer: 115 degrees

2Using: Vertically Opposite

Two lines intersect. If one angle is 40 degrees, find the vertically opposite angle.

Step 1: Vertically opposite angles are equal.

Step 2: The angle = 40 degrees.

Answer: 40 degrees

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More Class 8 ICSE Formulas

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Frequently Asked Questions

How many formulas are in Class 8 ICSE Linear Equations in One Variable?+
There are 3 formulas in the Linear Equations in One Variable chapter for Class 8 ICSE. Each formula is essential for solving problems in this topic.
How to remember Linear Equations in One Variable formulas easily?+
Practice regularly with worked examples, group related formulas together, and use SparkEd's interactive practice mode to reinforce your memory through problem-solving.
Are these Linear Equations in One Variable formulas enough for exams?+
Yes, these formulas cover the complete ICSE Class 8 syllabus for Linear Equations in One Variable. Practice applying them to different types of questions for full exam readiness.

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