Table of Contents

## What is a line ?

A line is a two-dimensional figure that has length but no width. It is created by a point that moves continuously in one direction.

## Different types of lines

There are different types of lines that can be drawn in a drawing or painting. Some of the most common lines are outlined lines, hatched lines, and contour lines.

Outlined lines are simply lines that are drawn around the edge of an object. They can be thick or thin, and can be any color. Outlined lines are often used to create borders or outlines around objects.

Hatched lines are lines that are drawn in a series of short, parallel lines. They can be any color, and can be thick or thin. Hatched lines are often used to create textures or patterns.

Contour lines are lines that are drawn around the outside of an object, but they are also drawn inside the object too. They are used to create a three-dimensional effect, and can be thick or thin. Contour lines are usually black, but they can be any color.

## How to Find the Equation of a Straight Line that is Parallel to One of the Coordinate Axes.

To find the equation of a straight line that is parallel to one of the coordinate axes, use the following formula:

Ax + By = C

## How to Find the Equation of a Straight that Cuts Off a Given Intercept on the Axis of Y and is Inclined at an Angle to the X-axis.

If the equation of the line is y = mx + b, then the equation of the line is:

y =mx + b + a

Where a is the angle of inclination.

## Solved Example

The average of five numbers is 15. What are the numbers?

The numbers are 8, 9, 10, 11, and 15.

## How to Find the Equation of a Straight Line in Terms of Perpendicular which Falls Upon it from the Origin and the Angle Which this Perpendicular Makes with the X-axis.

The equation of a straight line in terms of perpendicular which falls upon it from the origin and the angle which this perpendicular makes with the x-axis can be found using the following steps:

1. Determine the slope of the line using the formula:

m = (y 2 – y 1 )/(x 2 – x 1 )

2. Use the slope and the coordinates of two points on the line to find the equation of the line using the formula:

y = mx + b

3. Plug in the values for the slope and the coordinates of the two points to find the equation of the line.