X- and Y- Intercepts

Objective: To identify the x- and y- intercepts.

Standard 6.0

Return Quizzes

Any questions? 13 total points 2 extra credit points for last question

Intercepts

X-Intercept: where the line crosses the x-axis ordered pair: (x,0)

Y-Intercept: where the line crosses the y-axis Ordered pair: (0,y)

Y-intercept

X-intercept

Example 1 State the x- and y- intercepts

x-intercept:

y-intercept:

(-4,0)

(0,2)

TOO State the x- and y- intercepts

x-intercept:

y-intercept:

(3,0)

(0,6)

Example 3 State the x- and y- intercepts

x-intercept:

y-intercept:

(5,0)

none

Will this vertical line ever cross

the y-axis?no

Cover up Method!

If an equation is in standard form

ax + by = c a,b,c are all #’s

Cover up method: To find x-intercept, cover up the y To find y-intercept, cover up the x

Example: 5x + 4y = 20

y-intercept: (0,5)

x-intercept: (4,0)

Examples 5 & 6

6x + 3y = -18y-intercept: (0,-6)

x-intercept: (-3,0)

x – 4y = 14y-intercept: (0,-7/2)

x-intercept: (14,0)

TOO

Write the x- and y- intercepts as ordered pairs

3y = 2x + 12 5x – 3y = 20

(0,4) (-6,0)20

(0, )(4,0)3

Review – Write an equation in

point-slope

(-4,3) m = 1

7

(6,-2)(5,7)

Review – Write an equation in

Standard Form

(5,-15)(11,-3) y+5 = -4(x+1)

Review – Write an equation in

Standard Form

(8,-7) m = undefined (9,-2) m = 0

Homework

Pg. 350 #19-21 a & b, 22-27 Write the intercepts as an ordered pair

X-intercept: (#,0) Y-intercept: (0,#)

Monster Problem Time!!