So Who’s Confused

??

1.) Write an equation of a line givenThe points (1,6) & (3,-4)1.) Find the Slope

•m = (-4 -6)/(3-1)•m = -10/2 = -5

Write an equation of a line givenThe points (1,6) & (3,-4)

2.) Plug in one of the points (y - y1) = m(x - x1)

• (y - 6) = -5(x - 1) • y - 6 = -5x + 5

Write an equation of a line given y - 6 = -5x + 5y - 6 + 6 = -5x + 5 + 6 y = -5x + 11

So which one is an equation of the line??

y - 6 = -5x + 5y = -5x + 11

Today’s ObjectiveTo be able to Re-Write and equation in Standard Form.

Ax + By = C…… whereA,B & C are real numbers

Equations of LinesVertical line x = #Horizontal line y = #Slope, y-intercept y=mx+b Point, Slope y-y1=m(x-x1)Standard Form Ax+By = C

1.) Writing an equation in Standard Form Ax + By = C y = 2/5x - 3•The 1st step is to multiply both sides by 5.

1.) Writing an equation in Standard Form Ax + By = C y = 2/5x - 3• (5)y = (2/5x - 3)5• 5y = 2x - 15• 5y -2x = 2x -2x - 15•-2x + 5y = -15

Writing an equation in Standard Form Ax + By = C y = 1/2x + 4•The 1st step is to multiply both sides by 2.

You Try This One

Writing an equation in Standard Form Ax + By = C y = 1/2x + 4• (2)y = (1/2x + 4)2• 2y = x + 8• 2y -x = x -x + 8• -x + 2y = 8

2.) Writing an equation in Standard Form Ax + By = C y = 0.55x + 1.35

•The 1st step is to multiply both sides by 100.

2.) Writing an equation in Standard Form Ax + By = C y = 0.55x + 1.35•(100) y = (0.55x + 1.35)100• 100y = 55x + 135•100y -55x = 55x -55x + 135•-55x + 100y = 135

-55x + 100y = 135Since all 3 TERMS are divisible by 5, we can simplify by dividing both sides by 5.

(-55x + 100y)/5 = 135/5

-11x + 20y = 27

Writing an equation in Standard Form Ax + By = C y = 0.7x + 1.3•The 1st step is to multiply both sides by 10.

You Try This One

2.) Writing an equation in Standard Form Ax + By = C y = 0.7x + 1.3• (10) y = (0.7x + 1.3)10• 10y = 7x + 13• 10y -7x = 7x -7x + 13•-7x + 10y = 13

Write the equation1.) (3,4) m = 6 y - y1 = m(x - x1) y - 4 = 6(x - 3) y - 4 = 6x - 18y - 4 + 4 = 6x - 18 + 4 y = 6x - 14

Write the equation2.) y-intercept = 3, slope=2

y = 2x + 3

Write the equation3.) (6,-2) & (-4, 4)m = (4 - -2)/(-4 - 6)m = 6/-10 = - 3/5y - y1 = m(x - x1)y - 4 = -3/5(x - -4)

Write the equation y - 4 = -3/5(x - -4) y - 4 = -3/5x - 12/5y - 4 + 4= -3/5x - 12/5 + 4

y = -3/5x + 8/5