Today’s Objective

•To be able to find the x and y intercepts of an equation and use them to draw a quick graph.

The Intercepts

Y-Intercept =(0,6)

X-Intercept =(2,0)

The intercepts are

where the line crosses

the axis.

Finding the intercepts•3x + y = 6 To find the x-intercept,

let y = 0•3x + (0) = 6•3x = 6

Finding the intercepts•3x + y = 6 To find the y-intercept,

let x = 0•3(0) + y = 6• y = 6 (0,6)

The graph of 3x + y = 6

x-intercept =( 2,0)y-intercept =(0, 6)

Compare the 2 graphs3x+ y = 6

(1,3)

(0,6) (2,0)

(-1,9)

3x+ y = 6

x-intercept = 2y-intercept = 6

Finding the intercepts•x + 5y = 10 To find the x-intercept,

let y = 0•x + 5(0) = 10•x = 10 (10,0)

Finding the intercepts•x + 5y = 10 To find the y-intercept,

let x = 0•0 + 5y = 10•5y = 10

The graph of x + 5y = 10

x-intercept = (10,0)y-intercept = (0,2)

Find the intercepts and graph

•3x + 4y = 12

Finding the x-intercept•3x + 4y = 12•3x + 4(0) = 12•3x + 0 = 12•3x = 12•x = 4 (4,0)

Finding the y-intercept•3x + 4y = 12•3(0) + 4y = 12•0 + 4y = 12•4y = 12•y = 3 (0,3)

The graph of 3x + 4y = 12

x-intercept = (4,0)y-intercept =(0, 3)

Find the intercepts and graph

•y = 4x - 4

You try this one.

Finding the x-intercept•y = 4x - 4•0 = 4x - 4•0 + 4 = 4x -4 + 4•4 = 4x•1 = x (1,0)

Finding the y-intercept•y = 4x - 4•y = 4(0) - 4•y = -4•(0,4)

The graph of y = 4x - 4

x-intercept = (1,0)

y-intercept = (0,-4)