# GRAPHING LINES FROM POINTS

Learn how to graph a linear equation by choosing values for X, substituting them into an equation and getting a Y-value, then graphing those points on a coordinate plane.

This Algebra tutorial teaches students how to graph lines (linear equations) with a t-table.

In this video we look at graphing equations using a table of values.

## STANDARDS

Show that the graph of a function is the set of ordered pairs consisting of an input and the corresponding output.  (CCSS.8.F.1)

Interpret the equation y=mx+b as defining a linear function, whose graph is a straight line.  (CCSS.8.F.3)

# SLOPE FROM GRAPHS

How to, Given a Graph, Find the Slope.

Slope of a line Practice

In this lesson, students are asked to find the slope of a line given its graph. To find the slope of a line, students use the formula slope = rise over run.

## STANDARDS

Determine the rate of change and initial value of the function from a description of a relationship or from two (x,y) values, including reading these from a table or from a graph.  (8.F.4)

# SLOPE FROM POINTS

How to find the slope given two points.

This video shows how to find the slope of the line that passes through two points. So given the coordinates of two points, use the slope formula to find the slope. Keep in mind that this finds only the slope of the line passing through those two given points.

How to Find the Slope Given 2 Points.

## STANDARDS

Determine the rate of change and initial value of the function from a description of a relationship or from two (x,y) values, including reading these from a table or from a graph.  (8.F.4)

# SLOPE INTERCEPT FORM

Graphing a line in slope intercept form.

Point-slope and slope-intercept form from two points.

## STANDARDS

Derive the equation y=mx for a line through the origin and the equation y=mx+b for a line intercepting the vertical axis at b. (8.EE.6)

# SOLVING SYSTEMS BY GRAPHING

In this lesson, students learn to solve a system of linear equations by graphing.

Solving a system of linear equations by graphing. This topic is introduced and explained in simple terms from the ground up. From the Algebra 1 course by Derek Owens.

## STANDARDS

Analyze and solve pairs of simultaneous linear equations. (8.EE.8)

Solve systems of two linear equations in two variables algebraically, and estimate solutions by graphing the equations.  Solve simple cases by inspection. (8.EE.8b)

# SOLVING SYSTEMS BY SUBSTITUTION

How to Solve Systems of Linear Equations by Substitution.

MIT grad shows how to use the substitution method to solve a system of linear equations (aka. simultaneous equations). More videos with Nancy coming in 2017! To skip ahead: 1) For a BASIC SUBSTITUTION example, skip to time 0:19. 2) For an example where it's TRICKIER to solve and also involves FRACTIONS, skip to 08:17.

## STANDARDS

Analyze and solve pairs of simultaneous linear equations. (8.EE.8)

Solve systems of two linear equations in two variables algebraically, and estimate solutions by graphing the equations.  Solve simple cases by inspection. (8.EE.8b)

# SOLVING SYSTEMS BY ELIMINATION

PRACTICE - LEVEL 3

PRACTICE - LEVEL 4

MIT grad shows how to use the elimination method to solve a system of linear equations (aka. simultaneous equations).

Solving Systems of Equations by Elimination.

Systems of two equations in x and y can be solved by adding the equations to create a new equation with one variable eliminated. This new equation can then be solved to find the value of the remaining variable. That value is then substituted into either equation to find the value of other variable.

## STANDARDS

Analyze and solve pairs of simultaneous linear equations. (8.EE.8)

Solve systems of two linear equations in two variables algebraically, and estimate solutions by graphing the equations.  Solve simple cases by inspection. (8.EE.8b)