Starter Which pair of lines are parallel Which

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Starter Which pair of lines are parallel? Which pair of lines are perpendicular? How

Starter Which pair of lines are parallel? Which pair of lines are perpendicular? How do you know?

Which graph is parallel to y = 3 x + 6 y = -3

Which graph is parallel to y = 3 x + 6 y = -3 x - 6 y = 3 x - 2 How do you know?

Which graph is perpendicular to y = 3 x + 6 y = -3

Which graph is perpendicular to y = 3 x + 6 y = -3 x - 6 y = 3 x - 2 How do you know?

Which graph has the same y-intercept as y = 3 x + 6 y

Which graph has the same y-intercept as y = 3 x + 6 y = -3 x - 6 y = 3 x - 2 How do you know?

Which graph has the same x-intercept as y = 3 x + 6 y

Which graph has the same x-intercept as y = 3 x + 6 y = -3 x - 6 y = 3 x - 2 How do you know? Discuss: What is the x-intercept?

Here is the graph y = 3 x + 6: What is the y-intercept?

Here is the graph y = 3 x + 6: What is the y-intercept?

Here is the graph y = 3 x + 6: Where is the y-intercept

Here is the graph y = 3 x + 6: Where is the y-intercept found on the graph?

Here is the graph y = 3 x + 6: Where is the x-intercept

Here is the graph y = 3 x + 6: Where is the x-intercept found?

Here is the graph y = 3 x + 6: What is the x-intercept?

Here is the graph y = 3 x + 6: What is the x-intercept?

Here is the graph y = 3 x + 6: When we are given

Here is the graph y = 3 x + 6: When we are given a graph it is easy to read off the coordinate for the xintercept What can you say is always true about the x-intercept of any line? We know that the y coordinate at this point is 0: ( ? , 0 ) Discuss: How we could work out the x coordinate at this point if we don’t have a graph?

Where would y = 3 x + 6 cross the x-axis? We know that

Where would y = 3 x + 6 cross the x-axis? We know that when a line crosses the x-axis, the y coordinate is 0, so substitute y = 0 into the equation of the line. -6 0 = 3 x + 6 -6 -6 = 3 x ÷ 3 -2 = x Let’s check on Desmos ÷ 3 The line y = 3 x + 6 crosses the x-axis at -2 Its x-intercept is -2

Where would y = 2 x - 8 cross the x-axis? We know that

Where would y = 2 x - 8 cross the x-axis? We know that when a line crosses the x-axis, the y coordinate is 0, so substitute y = 0 into the equation of the line. +8 0 = 2 x - 8 +8 8 = 2 x ÷ 2 4=x ÷ 2 The line y = 2 x - 8 crosses the x-axis at 4 Its x-intercept is 4

On your whiteboards … Where does y = 2 x – 6 cross the

On your whiteboards … Where does y = 2 x – 6 cross the x-axis? We know that when a line crosses the x-axis, the y coordinate is 0, so substitute y = 0 into the equation of the line. +6 0 = 2 x - 6 +6 6 = 2 x ÷ 2 3=x ÷ 2 The line y = 2 x - 6 crosses the x-axis at 3 Its x-intercept is 3

On your whiteboards … Where would y = 6 x + 3 cross the

On your whiteboards … Where would y = 6 x + 3 cross the x-axis? We know that when a line crosses the x-axis, the y coordinate is 0, so substitute y = 0 into the equation of the line. -3 0 = 6 x + 3 -3 -3 = 6 x ÷ 6 -0. 5 = x ÷ 6 The line y = 6 x + 3 crosses the x-axis at -0. 5 Its x-intercept is -0. 5

On your whiteboards … Where would y = -2 x + 8 cross the

On your whiteboards … Where would y = -2 x + 8 cross the x-axis? We know that when a line crosses the x-axis, the y coordinate is 0, so substitute y = 0 into the equation of the line. -8 0 = -2 x + 8 -8 -8 = -2 x ÷-2 4=x ÷-2 The line y = -2 x + 8 crosses the x-axis at 4 Its x-intercept is 4

On your whiteboards … Where would y = -3 x - 12 cross the

On your whiteboards … Where would y = -3 x - 12 cross the x-axis? We know that when a line crosses the x-axis, the y coordinate is 0, so substitute y = 0 into the equation of the line. +12 0 = -3 x - 12 +12 12 = -3 x ÷-3 -4 = x ÷-3 The line y = -3 x - 12 crosses the x-axis at -4 Its x-intercept is -4

We know that when a line crosses the x-axis, the y coordinate is 0,

We know that when a line crosses the x-axis, the y coordinate is 0, so substitute y = 0 into the equation of the line. +3 ÷ 1/2 +3 6=x ÷ 1/2 Its x-intercept is 6

We know that when a line crosses the x-axis, the y coordinate is 0,

We know that when a line crosses the x-axis, the y coordinate is 0, so substitute y = 0 into the equation of the line. -2 -2 ÷ 1/4 -8 = x Its x-intercept is -8

On your whiteboards … Where would 2 y = 3 x + 2 cross

On your whiteboards … Where would 2 y = 3 x + 2 cross the x-axis? We know that when a line crosses the x-axis, the y coordinate is 0, so substitute y = 0 into the equation of the line. 2(0) = 3 x + 2 -2 -2 -2 = 3 x ÷ 3

Find the x-intercept of the following lines and make a sketch of each: 1)

Find the x-intercept of the following lines and make a sketch of each: 1) y = 4 x – 12 2) y = 6 x + 4 Challenge: 3) y = -2 x – 3 4 y = 2 x + 2 4) y = -3 - 3 x 5) y = ½x - 6

You will receive a set of cards and a grid. You will be asked

You will receive a set of cards and a grid. You will be asked about various attributes of the straight lines. For example: • which lines are parallel, • which have the same y-intercept etc… If you know you are going to have to compare the lines, what might be a good first step to prepare? Find the gradient and y-intercept for each card as your first step.

Complete the activity in your pairs. Put a pair of linear equations in each

Complete the activity in your pairs. Put a pair of linear equations in each box of the table. Make sure you justify each answer as you work and that both of you agree with what is being said. Create your own rule connecting the pair of lines that are left over. When you are happy with your answers, stick the equations into the table.

In pairs: The answer is y = 2 x + 5 What was the

In pairs: The answer is y = 2 x + 5 What was the question? Find as many as you can.

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Parallel Lines Introduction What are parallel lines LinesParallel Lines Introduction What are parallel lines Lines
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Parallel and Perpendicular Lines Parallel Lines Two linesParallel and Perpendicular Lines Parallel Lines Two lines
Parallel and Perpendicular Assignment Parallel Lines Parallel linesParallel and Perpendicular Assignment Parallel Lines Parallel lines
Proximity Closest pair divideandconquer Closest pair CLOSEST PAIRProximity Closest pair divideandconquer Closest pair CLOSEST PAIR
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Part 1 Coinciding Lines Parallel Lines Coinciding LinesPart 1 Coinciding Lines Parallel Lines Coinciding Lines
Relationships Between Lines Parallel Lines two lines thatRelationships Between Lines Parallel Lines two lines that
GEOMETRY Angles and Parallel Lines Intersecting Lines LinesGEOMETRY Angles and Parallel Lines Intersecting Lines Lines
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Relationships Between Lines Parallel Lines two lines thatRelationships Between Lines Parallel Lines two lines that
Lines Angles Parallel Lines Coplanar lines that dontLines Angles Parallel Lines Coplanar lines that dont
Lines and Angles Geometry PARALLEL LINES Two linesLines and Angles Geometry PARALLEL LINES Two lines
Parallel Perpendicular Lines Parallel and Perpendicular Lines TheParallel Perpendicular Lines Parallel and Perpendicular Lines The
Parallel Lines and Transversals Angles and parallel linesParallel Lines and Transversals Angles and parallel lines
PARALLEL LINES TRANSVERSA LS STUDENTS USE PARALLEL LINESPARALLEL LINES TRANSVERSA LS STUDENTS USE PARALLEL LINES
Parallel Lines cut by a Transversal Parallel LinesParallel Lines cut by a Transversal Parallel Lines
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Parallel Lines Transversals Parallel Lines and Transversals WhatParallel Lines Transversals Parallel Lines and Transversals What
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PARALLEL AND PERPENDICULAR LINES Slopes Parallel Lines ThePARALLEL AND PERPENDICULAR LINES Slopes Parallel Lines The