Linear Equations
Linear Graphs and EquationsUnderstanding Gradient
Sketching linear graphs
Identifying graphsWhat makes a linear equation LINEAR?An equation in one or more variables, each with an exponent of ONLY 1, where these variables are only added or subtracted. For ex :  2x + 7 = 15
4y + 5 = y + 15
3y = -4x + 12, Tentukannilai x jika y = 0 ! So with that definition Which of these equations are linear?x+y = 52x+ 3y = 47x-3y = 14y = 2x-2y=4 x2 + y = 5x = 5xy = 5x2 +y2 = 9y = x2y3
So with that definition Which of these equations are linear?LinearNot Linearx+y = 52x+ 3y = 47x-3y = 14y = 2x-2y=4 x2 + y = 5x = 5xy = 5x2 +y2 = 9y = x2y3
yxLinearNot LinearWhat is a Linear Equation?A linear equation is an equation whose graph is a LINE.
yxWhat is a Linear Equation?The equations we will be graphing have two variables, x and y.4For example,2A solution to the equation is any ordered pair (x , y) that makes the equation true.  -33-1-216The ordered pair (3 , 2) is a solution since,If we were to plot all these ordered pairs on a graph, we would be graphing a line.
yxThe x - values are picked by YOU!Graphing a Linear EquationHow do we graph linear equations?Let’s try this one:  y = 3x – 2Make a Table of values–8y = 3(–2) – 2 = –8Complete the table by inputting the x - values and calculating the corresponding y - values.–5y = 3(–1) – 2 = –5–2y = 3(0) – 2 = –21y = 3(1) – 2 = 14y = 3(2) – 2 = 4
yxGraphing a Linear EquationHow about another one!Let’s try x – 2y = 5.First Step:Write y as a function of xx – 2y = 5–2y = 5 – x
yxTake a moment and complete the chart…Click the screen when finishedGraphing a Linear EquationHow about another one!Let’s try x – 2y = 5.Second Step:Make a Table of Values–3–2
Sketching Linear GraphsWhat is y when x is 0?What is x when y is 0?We can now use this to get two sets of coordinates.
Sketching Linear Graphs2-4We know that our line must go through the points (0,-4) and (2,0)To draw a sketch of this graph, we just need to label the important points.
yxTake a moment and complete the chart…Click the screen when finishedGraphing a Linear EquationHow about another one!Let’s try 4x – 3y = 12To makes things easier:Make a Table of Values-134x – 3y = 120-40-4
yxGraphing Horizontal & Vertical LinesWhen you are asked to graph a line, and there is only ONE variable in the equation, the line will either be vertical or horizontal.  For example …Graph x = 3y =  –2Since there are no y – values in this equation, x is always 3 and y can be any other real number.  Graph y = –2Since there are no x – values in this equation, y is always – 2 and x can be any other real number.  x = 3
Exercise 1
SlopeParallel linesTheir slopes will be EQUAL.Perpendicular linesTheir slopes will be the   negative reciprocal of each other.
Increase in yGradient =Increase in xGradient / SlopeGradient tells us how steep something is.
For ex; Page 75This child doesn’t have a clue about gradient.
GradientIncrease in yGradient =Increase in xWhat is the gradient of the line?Gradient = 5/2 or 2.5
GradientIncrease in yGradient =Increase in xWhat is the gradient of this line?This time there is a decrease in yGradient = -2/4   or   -0.5
Exercise 2
yx4321-10123-1-2
Linear EquationsStandard Form	Ax + By = C				Ex ;  2x + y = 3Slope-intercept form	y = mx + bm = slope/gradientb = y-intercept
Contoh5x – 2y = 6 	(Standard Form)– 2y	= 6 – 5xy		= 6 – 5x		    – 2	y		=  6   –   5x		   – 2      – 2y	 	= - 3 + 5/2 x	     y = 5/2 x – 3 (Slope, y-Intercept)
Slope-intercept formy - interceptGradientEx ;     y = -2x + 3 (Slope, y-Intercept)Linear Graphs Form y = mxdan y = mx + bPage 84 - 87
MenentukanBentukPersamaanjikadiketahuigrafikVideo Contoh
Exercise 4
A Point and The Slope
Always find slope-intercept form first!Find the equation for the line containing the points (4, 2) and (3, 6).Find the slope using the formula.			m = 2 – 6 			       4 – 3  m = -4
(4, 2) and (3, 6)m = -42. Find the y-intercept.			y = mx + b			2 = -4 • 4 + b			2 = -16 + b18 = b
(4, 2) and (3, 6) m = -4   b = 183. Write equation in y = mx + b.y = -4x + 184. Convert to Ax + By = C.4x + y = 18
Linear EquationsBe able to form an equation given…		- slope and y-interceptex. m = -3 and b = 5		- a point and the slopeex. ( -4, -1 ) and m = ¾		- two pointsex. ( 0, -4 ) and ( -5, -2 )
MenentukanBentukPersamaanjikadiketahuigrafikVideo Contoh
Latihan 1
Latihan 2
Graph Form
Table form
Exercise 5
Relationship between Slope and Linear equations Pertemuan ke-6
y = -3/4 x – 6 Slope interceptFalling-3/4 -66/(-3/4) = - 8 -3/4 4/33x + 4y = -6The Equation FormDirectionSlopey-interceptx-interceptParallel SlopePerpendicular SlopeStandard Form
Given our 4 example equations identify all of the following…The Equation FormDirectionSlopey-interceptx-interceptParallel SlopePerpendicular SlopeFormy = ½ x + 5y  = -3x – 73x – 2y = 94x + 2y = 16x – 6y + 1 = 0
y = ½ x + 5Slope interceptRising½ 5-5/(½) = -10½ -2- x +2y = 5The Equation FormDirectionSlopey-interceptx-interceptParallel SlopePerpendicular SlopeStandard Form
y  = -3x – 7Slope interceptFalling-3 -7- -7/(-3) = -7/3-3 -73x + y = - 7The Equation FormDirectionSlopey-interceptx-interceptParallel SlopePerpendicular SlopeStandard Form
3x – 2y = 9StandardRising3/2 -4.5 or 9/233/2 -2/3y =3/2x + 9/2The Equation FormDirectionSlopey-interceptx-interceptParallel SlopePerpendicular SlopeSlope,intercept Form
4x + 2y = 16StandardFalling-2 84-2 1/2y = -2x + 8The Equation FormDirectionSlopey-interceptx-interceptParallel SlopePerpendicular SlopeSlope,Intercept Form
GeneralFalling½  2-1½  -2y = ½ x + 2The Equation FormDirectionSlopey-interceptx-interceptParallel SlopePerpendicular SlopeSlope,intercept Formx – 2y +4= 0
Exercise 6
Drawing with slope
SOAL 1Tentukanpersamaangaris yang  tegaklurusdengangaris4x – 3y– 6 = 0 danmelaluititik (2, -3)Jawab : Langkah 1 		CariGradien (m) denganmembuatpersamaangarisbentukgradienLangkah 2 Ingat !!! TegakLurus 					(Rubahgradiennya !!!)Langkah 3		gunakan y = mx + b
SOAL 2Hubungangaris3x + 4y – 6 = 0 dengangaris-6y = -8x +10 adalah…Jawab :Langkah 1		CarimdarikeduapersamaanLangkah 2		Sederhanakan, tentukansejajar/ berpotongantegaklurus !
Soal 3Garis 2x +5y – 2 = 0 sejajardengangaris 3ax – 4y – 2 = 0, tentukannilaia!Jawab :Langkah 1		CarimdaripersamaangarisygsudahdiketahuiLangkah 2		Ingat !!! m-nyaSejajarLangkah 3		padapersamaangaris 					3ax – 4y – 2 = 0, dibuatbentukgradienLangkah 4		Caria dari L.2 & L.3 !
Soal 4Tentukanpersamaangaris yang melaluititik (-2, -3 ) dantegaklurusdengangaris yang melaluititik( 2,3 ) dan (0, 1) Jawab ; Langkah 1		carimdarititik ( 2,3 ) dan(0, 1) Langkah 2		ingattegaklurus m-nyadirubah !!!Langkah 3		cari b dengan y = mx + bLangkah 4		BentukPersamaanGaris !
Soal 5Tentukanpersamaangaris yang melaluititik (-2, 1 ) dansejajardengangaris yang melaluititik ( 4,3 ) dan (-2,-5) Jawab ; Langkah 1		carimdarititik ( 2,3 ) 					dan (0, 1) Langkah 2		ingatSejajarm-nyaTetapLangkah 3		cari b dengan y = mx + bLangkah 4		BentukPersamaanGaris !

Linear equations

  • 1.
  • 2.
    Linear Graphs andEquationsUnderstanding Gradient
  • 3.
  • 4.
    Identifying graphsWhat makesa linear equation LINEAR?An equation in one or more variables, each with an exponent of ONLY 1, where these variables are only added or subtracted. For ex : 2x + 7 = 15
  • 5.
    4y + 5= y + 15
  • 6.
    3y = -4x+ 12, Tentukannilai x jika y = 0 ! So with that definition Which of these equations are linear?x+y = 52x+ 3y = 47x-3y = 14y = 2x-2y=4 x2 + y = 5x = 5xy = 5x2 +y2 = 9y = x2y3
  • 7.
    So with thatdefinition Which of these equations are linear?LinearNot Linearx+y = 52x+ 3y = 47x-3y = 14y = 2x-2y=4 x2 + y = 5x = 5xy = 5x2 +y2 = 9y = x2y3
  • 9.
    yxLinearNot LinearWhat isa Linear Equation?A linear equation is an equation whose graph is a LINE.
  • 10.
    yxWhat is aLinear Equation?The equations we will be graphing have two variables, x and y.4For example,2A solution to the equation is any ordered pair (x , y) that makes the equation true. -33-1-216The ordered pair (3 , 2) is a solution since,If we were to plot all these ordered pairs on a graph, we would be graphing a line.
  • 11.
    yxThe x -values are picked by YOU!Graphing a Linear EquationHow do we graph linear equations?Let’s try this one: y = 3x – 2Make a Table of values–8y = 3(–2) – 2 = –8Complete the table by inputting the x - values and calculating the corresponding y - values.–5y = 3(–1) – 2 = –5–2y = 3(0) – 2 = –21y = 3(1) – 2 = 14y = 3(2) – 2 = 4
  • 12.
    yxGraphing a LinearEquationHow about another one!Let’s try x – 2y = 5.First Step:Write y as a function of xx – 2y = 5–2y = 5 – x
  • 13.
    yxTake a momentand complete the chart…Click the screen when finishedGraphing a Linear EquationHow about another one!Let’s try x – 2y = 5.Second Step:Make a Table of Values–3–2
  • 14.
    Sketching Linear GraphsWhatis y when x is 0?What is x when y is 0?We can now use this to get two sets of coordinates.
  • 15.
    Sketching Linear Graphs2-4Weknow that our line must go through the points (0,-4) and (2,0)To draw a sketch of this graph, we just need to label the important points.
  • 17.
    yxTake a momentand complete the chart…Click the screen when finishedGraphing a Linear EquationHow about another one!Let’s try 4x – 3y = 12To makes things easier:Make a Table of Values-134x – 3y = 120-40-4
  • 18.
    yxGraphing Horizontal &Vertical LinesWhen you are asked to graph a line, and there is only ONE variable in the equation, the line will either be vertical or horizontal. For example …Graph x = 3y = –2Since there are no y – values in this equation, x is always 3 and y can be any other real number. Graph y = –2Since there are no x – values in this equation, y is always – 2 and x can be any other real number. x = 3
  • 20.
  • 21.
    SlopeParallel linesTheir slopeswill be EQUAL.Perpendicular linesTheir slopes will be the negative reciprocal of each other.
  • 22.
    Increase in yGradient=Increase in xGradient / SlopeGradient tells us how steep something is.
  • 23.
    For ex; Page75This child doesn’t have a clue about gradient.
  • 24.
    GradientIncrease in yGradient=Increase in xWhat is the gradient of the line?Gradient = 5/2 or 2.5
  • 25.
    GradientIncrease in yGradient=Increase in xWhat is the gradient of this line?This time there is a decrease in yGradient = -2/4 or -0.5
  • 27.
  • 29.
  • 30.
    Linear EquationsStandard Form Ax+ By = C Ex ; 2x + y = 3Slope-intercept form y = mx + bm = slope/gradientb = y-intercept
  • 32.
    Contoh5x – 2y= 6 (Standard Form)– 2y = 6 – 5xy = 6 – 5x – 2 y = 6 – 5x – 2 – 2y = - 3 + 5/2 x y = 5/2 x – 3 (Slope, y-Intercept)
  • 33.
    Slope-intercept formy -interceptGradientEx ; y = -2x + 3 (Slope, y-Intercept)Linear Graphs Form y = mxdan y = mx + bPage 84 - 87
  • 35.
  • 36.
  • 37.
    A Point andThe Slope
  • 38.
    Always find slope-interceptform first!Find the equation for the line containing the points (4, 2) and (3, 6).Find the slope using the formula. m = 2 – 6 4 – 3 m = -4
  • 39.
    (4, 2) and(3, 6)m = -42. Find the y-intercept. y = mx + b 2 = -4 • 4 + b 2 = -16 + b18 = b
  • 40.
    (4, 2) and(3, 6) m = -4 b = 183. Write equation in y = mx + b.y = -4x + 184. Convert to Ax + By = C.4x + y = 18
  • 41.
    Linear EquationsBe ableto form an equation given… - slope and y-interceptex. m = -3 and b = 5 - a point and the slopeex. ( -4, -1 ) and m = ¾ - two pointsex. ( 0, -4 ) and ( -5, -2 )
  • 42.
  • 44.
  • 45.
  • 46.
  • 47.
  • 48.
  • 49.
    Relationship between Slopeand Linear equations Pertemuan ke-6
  • 51.
    y = -3/4x – 6 Slope interceptFalling-3/4 -66/(-3/4) = - 8 -3/4 4/33x + 4y = -6The Equation FormDirectionSlopey-interceptx-interceptParallel SlopePerpendicular SlopeStandard Form
  • 52.
    Given our 4example equations identify all of the following…The Equation FormDirectionSlopey-interceptx-interceptParallel SlopePerpendicular SlopeFormy = ½ x + 5y = -3x – 73x – 2y = 94x + 2y = 16x – 6y + 1 = 0
  • 53.
    y = ½x + 5Slope interceptRising½ 5-5/(½) = -10½ -2- x +2y = 5The Equation FormDirectionSlopey-interceptx-interceptParallel SlopePerpendicular SlopeStandard Form
  • 54.
    y =-3x – 7Slope interceptFalling-3 -7- -7/(-3) = -7/3-3 -73x + y = - 7The Equation FormDirectionSlopey-interceptx-interceptParallel SlopePerpendicular SlopeStandard Form
  • 55.
    3x – 2y= 9StandardRising3/2 -4.5 or 9/233/2 -2/3y =3/2x + 9/2The Equation FormDirectionSlopey-interceptx-interceptParallel SlopePerpendicular SlopeSlope,intercept Form
  • 56.
    4x + 2y= 16StandardFalling-2 84-2 1/2y = -2x + 8The Equation FormDirectionSlopey-interceptx-interceptParallel SlopePerpendicular SlopeSlope,Intercept Form
  • 57.
    GeneralFalling½ 2-1½ -2y = ½ x + 2The Equation FormDirectionSlopey-interceptx-interceptParallel SlopePerpendicular SlopeSlope,intercept Formx – 2y +4= 0
  • 58.
  • 59.
  • 61.
    SOAL 1Tentukanpersamaangaris yang tegaklurusdengangaris4x – 3y– 6 = 0 danmelaluititik (2, -3)Jawab : Langkah 1 CariGradien (m) denganmembuatpersamaangarisbentukgradienLangkah 2 Ingat !!! TegakLurus (Rubahgradiennya !!!)Langkah 3 gunakan y = mx + b
  • 62.
    SOAL 2Hubungangaris3x +4y – 6 = 0 dengangaris-6y = -8x +10 adalah…Jawab :Langkah 1 CarimdarikeduapersamaanLangkah 2 Sederhanakan, tentukansejajar/ berpotongantegaklurus !
  • 63.
    Soal 3Garis 2x+5y – 2 = 0 sejajardengangaris 3ax – 4y – 2 = 0, tentukannilaia!Jawab :Langkah 1 CarimdaripersamaangarisygsudahdiketahuiLangkah 2 Ingat !!! m-nyaSejajarLangkah 3 padapersamaangaris 3ax – 4y – 2 = 0, dibuatbentukgradienLangkah 4 Caria dari L.2 & L.3 !
  • 64.
    Soal 4Tentukanpersamaangaris yangmelaluititik (-2, -3 ) dantegaklurusdengangaris yang melaluititik( 2,3 ) dan (0, 1) Jawab ; Langkah 1 carimdarititik ( 2,3 ) dan(0, 1) Langkah 2 ingattegaklurus m-nyadirubah !!!Langkah 3 cari b dengan y = mx + bLangkah 4 BentukPersamaanGaris !
  • 65.
    Soal 5Tentukanpersamaangaris yangmelaluititik (-2, 1 ) dansejajardengangaris yang melaluititik ( 4,3 ) dan (-2,-5) Jawab ; Langkah 1 carimdarititik ( 2,3 ) dan (0, 1) Langkah 2 ingatSejajarm-nyaTetapLangkah 3 cari b dengan y = mx + bLangkah 4 BentukPersamaanGaris !