Writing Linear Equations

What you need to write the equation of a line. A slope – Given to you – You must find A point – Y-intercept – Other point

Page 1 Given slope and y-intercept

Given slope and y-intercept (Given m and b) – Page 1 (0, 2) rise = 1 run = 2 Press pause

Given slope and y-intercept (Given m and b) – Page 1 m = b = (0, 2) y – y 1 = m( x – x 1 ) POINT – SLOPE FORM (x 1, y 1 ) y – 2 = ( x – 0) y – 2 = x – ●0 DISTRIBUTE y – 2 = x GET Y ALONE y = x YOUR ANSWER!! REPLACE Press pause

Given slope and y-intercept (Given m and b) – Page (0, 11) Press pause

Given slope and y-intercept (Given m and b) – Page 1 m = b = (0, 11) y – y 1 = m( x – x 1 ) POINT – SLOPE FORM (x 1, y 1 ) DISTRIBUTE GET Y ALONE +11 YOUR ANSWER!! REPLACE y – 11 = ( x – 0) y – 11 = x – ●0 y – 11 = x y = x + 11 Press pause

Given slope and y-intercept (Given m and b) – Page 1 Press pause 10 (0, 10)

Given slope and y-intercept (Given m and b) – Page 1 m = 10 b = (0, 10) y – y 1 = m( x – x 1 ) POINT – SLOPE FORM (x 1, y 1 ) DISTRIBUTE GET Y ALONE +10 YOUR ANSWER!! REPLACE y – 10 = 10 ( x – 0) y – 10 = 10 x – 10●0 y – 10 = 10 x y = 10 x + 10 Press pause

Page 2 Given slope and another point

Given slope and another point [Given m and (x,y)] – Page 2 rise = 3 run = 1 =3 (4, 2) (x 1, y 1 ) Press pause

m = 3 (x 1, y 1 ) = (4, 2) y – y 1 = m( x – x 1 ) POINT – SLOPE FORM DISTRIBUTE GET Y ALONE +2 YOUR ANSWER!! REPLACE y – 2 = 3 ( x – 4) y – 2 = 3 x – 3●4 y – 2 = 3 x – 12 y = 3 x – 10 Press pause Given slope and another point [Given m and (x,y)] – Page 2

+3 +2 (12, 13) (x 1, y 1 ) Press pause

m = y – y 1 = m( x – x 1 ) POINT – SLOPE FORM DISTRIBUTE GET Y ALONE +13 YOUR ANSWER!! REPLACE y – 13 = ( x – 12) y – 13 = x – ●12 y – 13 = x - 8 y = x + 5 Press pause (x 1, y 1 ) = (12, 13) Given slope and another point [Given m and (x,y)] – Page 2

Press pause 1.50 (20, 80) miles = x cost = y (x 1, y 1 )

m = 1.50 (x 1, y 1 ) = (20, 80) y – y 1 = m( x – x 1 ) POINT – SLOPE FORM DISTRIBUTE GET Y ALONE +80 YOUR ANSWER!! REPLACE y – 80 = 1.50 ( x – 20) y – 80 = 1.50 x – 1.50●20 y – 80 = 1.50 x – 30 y = 1.50 x + 50 Press pause Given slope and another point [Given m and (x,y)] – Page 2

Page 3 Given two points

Given two points [Given (x 1, y 1 ) and (x 2,y 2 )] – Page 3 (1,2) (5,3) (1,2) Press pause (x 1, y 1 )

m = y – y 1 = m( x – x 1 ) POINT – SLOPE FORM DISTRIBUTE GET Y ALONE +2 YOUR ANSWER!! REPLACE y – 2 = ( x – 1) y – 2 = x – ●1 y = x Press pause (x 1, y 1 ) = (1, 2) Given two points [Given (x 1, y 1 ) and (x 2,y 2 )] – Page 3 y – 2 = x -

Given two points [Given (x 1, y 1 ) and (x 2,y 2 )] – Page 3 Press pause (-5, 10) (x 1, y 1 )

m = y – y 1 = m( x – x 1 ) POINT – SLOPE FORM DISTRIBUTE GET Y ALONE +10 YOUR ANSWER!! REPLACE y – 10 = ( x – -5) y – 10 = x + ●5 y = x Press pause (x 1, y 1 ) = (-5, 10) Given two points [Given (x 1, y 1 ) and (x 2,y 2 )] – Page 3 y – 10 = x

Given two points [Given (x 1, y 1 ) and (x 2,y 2 )] – Page 3 days = x money = y Press pause (10, 600) (30, 1600) Slope calculation (10, 600) 50 (x 1, y 1 )

m = 50 y – y 1 = m( x – x 1 ) POINT – SLOPE FORM DISTRIBUTE GET Y ALONE +600 YOUR ANSWER!! REPLACE y – 600 = 50 ( x – 10) y – 600 = 50 x – 50●10 y – 600 = 50 x – 500 y = 50 x Press pause Given two points [Given (x 1, y 1 ) and (x 2,y 2 )] – Page 3 (x 1, y 1 ) = (10, 600)