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Ch 7 Graphs and Linear Equations. Review on Graphing. y. “origin” (0,0). Ordered Pair (x, y). x. Coordinate Plane. y. “origin” (0,0). Ordered Pair ( 5 , 4 ). x. Coordinate Plane. y. “origin” (0,0). Ordered Pair ( 5 , -4 ). x. Coordinate Plane. y. Ordered Pair ( -5 , -4 ).
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Ch 7 Graphs and Linear Equations Review on Graphing
y “origin” (0,0) Ordered Pair (x, y) x Coordinate Plane
y “origin” (0,0) Ordered Pair (5, 4) x Coordinate Plane
y “origin” (0,0) Ordered Pair (5, -4) x Coordinate Plane
y Ordered Pair (-5, -4) x Coordinate Plane
y Coordinates Ordered Pair (-5, 0) x (-5,0)
y (0,6) Graph (0, 6) I II second quadrant first quadrant x III IV third quadrant fourth quadrant quadrants Not in a quadrant if on either axis
y What are the coordinates? Which quadrant? I (1,1) x
y What are the coordinates? Which quadrant? II (-3, 3) x
y What are the coordinates? Which quadrant? x IV (5, -2)
y What are the coordinates? Which quadrant? x (0, -5) Not in a quadrant if on either axis
7.2 Graphing Equations Objectives: • Learn to determine if an ordered pair is a solution of an equation. • Graph equations using ordered pairs.
How do you determine if an ordered pair is a solution?? You plug in the (x, y) value into your x and y in the equations and see if the right side = the left
Determine if the ordered pair is a solution of the equation. y = 2x + 1 (3 ,7 ) 7 = 2(3) + 1 YES The ordered pair (3,7) is a solution.
Determine if the ordered pair is a solution of the equation. 4y - 3x = 22 (-2 ,4 ) 4(4) – 3 (-2)= 22 16 + 6 = 22 YES The ordered pair (-2,4) is a solution.
Determine if the ordered pair is a solution of the equation. y - 3x = -2 (-2 ,8 ) (8) – 3 (-2)= -2 ??? 8 + 6 -2 NO The ordered pair (-2,8) is not a solution.
Graphing Equations • We are going to learn three ways to graph a linear equation. Today we are going to learn how to graph by “Making a Table”
Making a Table • Solve the equation in y = format (slope intercept form) • Pick your x values (-1, 0,1) • Plug in the x values into x in the equation to find the corresponding y values • Plot the (x, y) ordered pairs on the coordinate plane
y x y Graph: y = x x
y Find 3 solutions y = 2x + 1 x 1 3 (1,3) 2(1) +1 1 0 2(0) +1 (0,1) -1 2(-1) +1 (-1,-1) -1
Solve for ‘y’ Solve for ‘y’ means “get y all by itself”
y Graph: -2x + y = 5 y = 2x + 5 x 1 2(1) +5 7 (1,7) 0 2(0) +5 5 (0,5) -1 2(-1)+5 3 (-1,3)
y Graph: -2x + 3y = 15 3y = 2x + 15 x Y=2/3x +5 3 7 (3,7) (2/3)(3) +5 0 5 (2/3) (0) +5 (0,5) -3 3 (2/3)(-3)+5 (-3,3)
y x y Graph: 3x - y = 2 3x = y + 2 3x - 2 = y x
Assignment:Page 311(2-26) even-Use graph paper- #’s 8-14 just make the table you do not have to graph-#’s 16-26 make the table and graph