# Algebra

### Equations and Gradients of a straight line

Equations and Gradients of a straight line What is a straight line? A straight line is a line with no curves. By definition we can say that a straight line is the set of all points between and extending beyond two points. Equation of a straight line An equation of the first degree of the […]

### Expanding and Factorising Algebraic Expressions

Expanding and Factorising Algebraic expressions What is an expansion? The process of re writing an algebraic expression that contains brackets by expanding them is called an expansion.To expand a bracket means to multiply each term in the bracket by the expression outside the bracket. Be careful! Watch out for negative numbers in front of brackets […]

### Algebraic Expressions

Algebraic expressions What is an algebraic expression? An algebraic expression is an expression which is built from variables, constants and the algebraic operations. Difference between algebraic expression and algebraic equation An algebraic expression is a mathematical phase that can contain numbers, variables and not an equal sing .They can´t be solved but they can be […]

### Simultaneous linear equations

Simultaneous linear equations What are simultaneous equations? Simultaneous equations are a set of two or more equations, each containing two or more variables whose values can simultaneously satisfy both or all the equations in the set, the number of variables being equal to or less than the number of equations in the set. Simultaneous linear […]

Quadratic equation What is a quadratic equation? A quadratic equation is an equation of degree 2 with one variable and that can be written as:x² + bx + c = 0, where a≠0, a, b, c are the coefficients and x is the variable.The number of roots of a quadratic equation is less or equal to the number of its degree.The graph of […]

### Equations. First degree equation

Powers and Roots An expression that represents repeated multiplication of the same factor is called a power. So, when we want to multiply a number by itself repeatedly we use powers. $displaystyle {{a}^{n}}$ tells  you  to multiply  a  by itself, exactly n-times. The exponent corresponds to the number of times the base is used as […]