Worked example
Solve and verify a linear equation
Solve 3x + 5 = 20 and check the answer.
- Subtract 5 from both sides: 3x = 15.
- Divide both sides by 3: x = 5.
- Check: 3(5) + 5 = 20, so both sides are equal.
Answer x = 5.
Mathematics
Algebra
Use variables, expressions and equations to represent relationships.
Understand the concept
Algebra uses letters such as x or y to represent numbers that may vary or are not yet known. Expressions describe calculations, while equations state that two expressions have the same value.
From Grades 7 to 10, algebra develops from combining like terms to solving linear equations, using identities and working with polynomials. The central idea is to follow valid operations while keeping every equation balanced.