# Chapter 4.Linear Equations in Two variables

**1. **An equation of the form *ax *+ *by *+ *c *= 0, where *a*, *b *and *c *are real numbers, such that *a *and

*b *are not both zero, is called a linear equation in two variables.

**2. **A linear equation in two variables has infinitely many solutions.

**3. **The graph of every linear equation in two variables is a straight line.

**4. ***x *= 0 is the equation of the *y*-axis and *y *= 0 is the equation of the *x*-axis.

**5. **The graph of *x *= *a *is a straight line parallel to the *y*-axis.

**6. **The graph of *y *= *a *is a straight line parallel to the *x*-axis.

**7. **An equation of the type *y *= *mx *represents a line passing through the origin.

**8. **Every point on the graph of a linear equation in two variables is a solution of the linear

equation. Moreover, every solution of the linear equation is a point on the graph of the linear equation.