1. Your Turn Rewrite 5x + y = 8 so y is a function of x Find the slope:
2) (–5, 6) and (0, 8)
3) (–4, 2) and (–4, 6)
4) (9, 0) and (5, 0)

2. Worksheet Key

3. _Intercepts Section 3.3 Section 3.3 Section 3.3 12/9/2018 9:12 AM
4.3: Graph Using Intercepts

4. Definitions Linear Standard Equation is: Ax + By = C
X-Intercept (Ax = C) value of x when y = 0
Y-Intercept (By = C) value of y when x = 0
2 ways of finding graphs quickly
“Cover-Up” Method
Slope-Intercept Form

5. Solving for Intercepts
Make sure it is in Linear Standard Form: Ax + By = C
To get the x-intercept, cover up the y terms by isolating it.
MUST LABEL IT AS A POINT and NOT AS AN EQUATION
Solve for x.
Do the same for y-intercept, cover up the x terms and solve for y.

6. Example 1 Find x- and y-intercept of the graph, 3x + 4y = 12.
What’s leftover?
What’s leftover?

7. Example 1 Find x- and y-intercept of the graph, 3x + 4y = 12. (0, 3)
(4, 0)
x-intercept: (0, 4)

8. Example 2
Find x- and y-intercept of the graph, 2x + 7y = 28.

9. Example 3
Find x- and y-intercept of the graph, 4x – 2y = 10.

10. Your Turn
Find x- and y-intercept of the graph, –3x + 5y = –15.

11. Example 4 Find x- and y-intercept of the graph, y = 4x + 10.
What’s leftover?
What’s leftover?

12. Example 5
Find x- and y-intercept of the graph, y = –2 + 8x.

13. Example 6
Find x- and y-intercept of the graph, y = 3/5x – 12.

14. Your Turn
Find x- and y-intercept of the graph, y = –14x + 7.

15. Example 7 Graph 4x – 3y = 12 and find x- and y-intercept.
What’s leftover?
What’s leftover?

16. Example 7 Graph 4x – 3y = 12 and find x- and y-intercept. (0, 4)
(3, 0)
x-intercept

17. Example 8
Graph –7x + 6y = 42 and find x- and y-intercept.

18. Your Turn
Graph x – 12y = 6 and find x- and y-intercepts.

19. Example 9
You are helping to plan an awards banquet for your school, and you need to rent tables to seat 180 people. Tables come in two sizes, small tables that seat 4 people and large tables that seat 6 people. This situation can be modeled by 4x + 6y = 180 where x is the number of small tables and y is the number of large tables. Find the intercepts, graph the equation, and plot at least 4 possibilities.
Find the Intercepts:

20. Example 9
You are helping to plan an awards banquet for your school, and you need to rent tables to seat 180 people. Tables come in two sizes, small tables that seat 4 people and large tables that seat 6 people. This situation can be modeled by 4x + 6y = 180 where x is the number of small tables and y is the number of large tables. Find the intercepts, graph the equation, and plot at least 4 possibilities.
Find the Intercepts:
(Each line is 5 points)
(0, 30)
y-intercept
(15, 20)
(45, 0)
x-intercept
(30, 10)

21. Your Turn
You make and sell bows. You sell small bows for $3 and large bows for $5. You want to earn $60. The equation is 3x + 5y = 60 where x is the number of small bows and y is the number of small bows. Find the intercepts, graph the equation, and identify at least 3 possibilities.
(0, 30)
y-intercept
(10, 6)
(45, 0)
x-intercept

22. Assignment
Worksheet