Review the key concepts, formulae, and examples before starting your quiz.
🔑Concepts
A variable is a letter or symbol used to represent an unknown number or a quantity that can change. Common variables include .
Constants are values that do not change, such as .
An algebraic expression is formed by combining variables and constants using operations like addition (), subtraction (), multiplication (), and division ().
Patterns in geometry can be expressed using variables. For example, if the side of a square is , its perimeter is always .
Number patterns can be generalized. If represents the position of a term in a sequence, the term can often be written as an expression in .
Rules for properties of numbers such as Commutativity and Distributivity can be expressed using letter-numbers: and .
Terms are added to form expressions. For example, in , the terms are and .
The numerical factor in a term is called its coefficient. In the term , the coefficient is .
📐Formulae
💡Examples
Problem 1:
Observe the pattern of matchsticks used to form the letter 'L'. One 'L' requires sticks, two 'L's require sticks, and three 'L's require sticks. Write a general rule for the number of sticks required for 'L's.
Solution:
Explanation:
Since each 'L' requires matchsticks, for such shapes, the total sticks needed is . Here is the variable representing the number of shapes.
Problem 2:
Find the rule for the term of the number pattern:
Solution:
Explanation:
The terms are multiples of . For the term (), . For the term (), . Thus, the general relationship is .
Problem 3:
Identify the terms and their coefficients in the expression .
Solution:
Terms: . Coefficients: .
Explanation:
Terms are the parts separated by or signs. The coefficient is the numerical multiplier of the variables in each term.
Problem 4:
If the side of a regular hexagon is denoted by , express the perimeter of the hexagon using .
Solution:
Explanation:
A regular hexagon has equal sides. If one side is , the sum of all sides is .