Algebra 1 Common Core Student Edition, Grade 8-9

downward. If the line had a positive slope, sloping
upward, then the point ( 1 , 2 ) would be above the line
and would satisfy y> mx + b, which is not what is
given. 43. G 45. 96 days

46. 2 < x < 7 <i i i—i i cd i -+*
    -3 -101


47. one solution: ( - 6 , - 9 ) 48. one solution: (2, 0)


48. no solution

Lesson 6-6

Go t It?

pp. 400-405

2a

y

m

! ; | VMs.

\s X

y< -jx + 1

y < 1* + 1

b. No; the red line is dashed

so points on that line are

not included in the

solution.

2 x+ 2 y < 126,

x< 50, y> 10

0 10 30 50 70

4. You can substitute the ordered pair into each inequality
   to make sure that it makes each true. 5. Not necessarily;
   as long as there is some overlap of the half-planes, then
   the system will have a solution. 6. You need to find the
   intersection of each of the two systems, but the intersections
   of lines will be a point or line and the intersections of
   inequalities will be a line or a planar section.

Ex e r c i se s 7. yes 9. no

(^11) y4i
/ i
f/
//
J
/
' { X
t :> L
/ 7 /
I/
y
I t

13. 
    

    
    

    V

    
    

    
    

4- V X

— \ *

V

15. 
    
    
    
    17. 
        
    
    
    
    


16. y
    \

21.

-5-

3

IH

/

I

1 -

»

/

X

0 t

/

X

2 3. y < x + 2, y < -\x 25.y>2,y>x+1

2 7. Let x = hours driven by slower driver, let y = hours

driven by faster driver.

29a. y 4 f

/

/ X

—■ / (^0) /
/
/!
/
t
b. No; they have the same
slope and different
y-intercepts, so they will
never intersect, c. no
d. No; there are no points
that satisfy both
inequalities.

31. You can buy 5 T-shirts and 1 dress shirt or 2 T-shirts
    and 3 dress shirts. 33. C 3 5. Check students' work.


32. The graph shows two lines, one passing through (1,1)

c

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