Review the key concepts, formulae, and examples before starting your quiz.
๐Concepts
The word 'Algebra' is derived from the title of the book 'Al-Kitab al-mukhtasar fi hisab al-jabr waโl-muqabala' written by the Persian mathematician Al-Khwarizmi. 'Al-Jabr' means the restoration of broken parts.
Indian mathematicians like Aryabhata and Brahmagupta used 'Beejganit' to refer to algebra. They developed methods to solve linear equations of the form .
An algebraic equation is a condition on a variable. It says that two expressions are equal. For example, in , the Left Hand Side (LHS) is and the Right Hand Side (RHS) is .
Balancing Method: An equation remains unchanged if the same number is added to or subtracted from both sides, or if both sides are multiplied or divided by the same non-zero number.
Transposition Method: Moving a term from one side of the equation to the other is called transposition. During transposition, the sign of the term changes: becomes , becomes , becomes , and becomes .
๐Formulae
๐กExamples
Problem 1:
Solve for : .
Solution:
Explanation:
We first transpose to the RHS, where it becomes . Then, we transpose the coefficient (which is multiplying ) to the RHS, where it divides .
Problem 2:
A number is such that when is subtracted from it, the result is . Find .
Solution:
Explanation:
The problem is translated into the equation . By transposing to the RHS, we add it to to find the value of .
Problem 3:
Find the value of in the equation .
Solution:
Explanation:
We transpose the large constant to the RHS and perform vertical subtraction to find the unknown variable .