# Introduction to linear equations

### Introduction to linear equations

This is a lesson that teaches how to determine if an expression is a linear equation; and how to graph a linear equation.

#### Lessons

Expression: A collection of numbers, variables, and signs, such as $3, 3x+4, 5 x^2 + 2, \sqrt{x-3},$etc

Equations: A mathematical statement with an equal sign, such as $y = 2, y = 3x-2, y = x, x = 3,$etc

Linear
Equation
: Ax + By = C (A, B & C are constants; x & y are variables)
All linear equations are functions except a vertical line such as x = 3.
• Introduction
a)
What is a linear equation?

• 1.
Which of the following is a linear equation?
i)
x = 4
ii)
y = 2
iii)y = 3x + 5

• 2.
Graph the linear equations:
a)
y = -${3 \over 4}$x + 2

b)
y = ${4 \over 5}$x$-2$

c)
${3 \over 4}x + 0.6y =3$