Bridge to Algebra 2 A Semester Exam Review Answers 2015-2016

Bridge to Algebra 2 A
Exam Review Answers
Bridge to Algebra 2 A
Semester Exam Review Answers
2015-2016
MCPS © 2015–2016
Bridge to Algebra 2 A
Exam Review Answers
1.
a.
b.
c.
2.
About 66 or 67 births that result in twins
3.
a.
b.
15 pounds
6 cups
$19.47
20 gallons
5
 0.833 gallons/hour
6
c.
60 gallons
d.
7
4.
Crystal’s
5.
Player 1:
Player 2:
Player 3:
Player 4:
1
days
2
.324 batting average
.322 batting average
.320 batting average
.334 batting average
Player 4 is the best hitter because he has the highest ratio of hits to number of
times at bat.
6.
a.
b.
I
II
7.
a.
b.
8
–6
c.
 9,10 or 9  x  10
d.
 6,8 or 6  y  8
e.
 9, 7   3, 1
f.
 7, 3  1,10
or 9  x  7  3  x  1
or 7  x  3 1  x  10
For 7e and 7f, open intervals are acceptable.
p
p  2l
 l or w 
2
2
8.
w
9.
x  2  y  r  or x  2 y  2r
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Bridge to Algebra 2 A
10.
1
vm
t  (v  m) or t 
4
4
11.
x  3
12.
x 8
13.
x
14.
x  3
15.
x  3
Exam Review Answers
5
 0.625
8
-8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8
16.
x3
-8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8
17.
x 8
-8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8
18.
x  3
-8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8
19.
B
20.
a.
15  .75x  18
b.
x4
c.
Paolo’s large pizza with 0, 1, 2, or 3 toppings is less expensive than Pete’s
large pizza with any number of toppings.
21.
P  30  45 x where x is the number of hours
22.
a.
b.
c.
6  4 x  20
x  3.5
You will still have to walk 1.5 miles to get to school.
MCPS © 2015–2016
Bridge to Algebra 2 A
Exam Review Answers
The taxi ride will take you 1.5 miles from school. (other answers
possible)
23.
Line 4
24.
y-intercept = 80
Equation: y  80  65 x
Table:
Graph:
Miles
from
Home
80
145
210
275
340
405
# of Miles From Home (y)
Hours
Since
Noon
0
1
2
3
4
5
# of Hours since Noon (x)
b.
Marina is 80 miles from home at noon.
c.
slope (rate of change) = 65
Equation: y  80  65 x
1
1
1
1
1
Graph:
Hours
Since
Noon
0
1
2
3
4
5
Miles
from
Home
80
145
210
275
340
405
65
65
65
65
65
# of Miles From Home (y)
Table:
Run = 1
Rise = 65
# of Hours since Noon (x)
d.
Marina is traveling at a constant rate (speed) of 65 miles per hour.
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Bridge to Algebra 2 A
MCPS © 2015–2016
Exam Review Answers
Bridge to Algebra 2 A
a.
y-intercept = 500
Equation:
5
y  500  x
6
Table:
Graph:
Number of
Hours since
Leak Began
Number of
Gallons
Remaining in
Tank
0
1
500
1
499
6
495
490
485
480
6
12
18
24
Number of Gallons Remaining in Tank (y)
25.
Exam Review Answers
Number of Hours since Leak Began (x)
b.
The tank contains 500 gallons of water when the leak occurs.
5
slope (rate of change) = 
c.
6
5
Equation:
y  500  x
6
Table:
5
6
6
6
Number of
Hours since
Leak Began
Number of
Gallons
Remaining in
Tank
0
1
500
6
12
18
24
495
490
485
480
–5
–5
–5
Number of Gallons Remaining in Tank (y)
1
Graph:
–5
6
Number of Hours since Leak Began (x)
d.
The water leaks out of the tank at a steady rate of
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5
gallons per hour.
6
Bridge to Algebra 2 A
Exam Review Answers
26.
No
When x  1, and x  5, y has 2 different values.
27.
Yes
Every x has exactly one y.
28.
No
The vertical line test shows that some x’s have two y’s.
29.
Yes
The vertical line test shows that every x has exactly one y.
30.
32.
31.
x
y
–3
–2
–1
0
1
2
3
5
3
1
–1
–3
–5
–7
Number of
Cups of Juice
Concentrate, x
0
1
2
3
4
5
6
a.
fish per week
b.
0  x  3 , 3  x  5 , 5  x  10
c.
500 x  2000, if 0  x  3

f  x   500,
if 3  x  5
50 x  250,
if 5  x  10

Number of
Cups of Water,
y
0
1.5
3
4.5
6
7.5
9
d.
– 500 , 0,
e.
– 250 fish per week
f.
While there was actual variation in the slope during the time interval x  1
to x  5 , by the end of the 4 weeks, there were 1000 fewer fish than at the
1000 fish 250 fish

 250 fish/week
beginning of those four weeks.
4 weeks
1 week
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50
Bridge to Algebra 2 A
Exam Review Answers
b.
c.
No equation. This could be represented by 2300 x  400 y which is an
expression, not an equation.
IV
I
34.
a.
b.
c.
II
VI
V
35.
a.
y  0.256 x  25.879
b.
0.256 feet per year.
c.
According to the regression line, the cliff erodes 0.256 feet each year.
That is, the distance from the house to the edge of the cliff decreases by
0.256 feet each year.
d.
25.879
e.
According to the regression line, the distance from the house to the edge
of the cliff was 25.879 feet in 1975.
f.
15.639 feet
g.
The year 2076.
36.
a.
b.
c.
d.
e.
f.
Graph 1
Graph 3
Graph 2
Graph 3
Graph 4
Graph 2
37.
x  1 , y  2 . This could also be written as the point 1, 2  .
38.
x  4 , y  0 . This could also be written as the point  4, 0  .
33.
a.
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Bridge to Algebra 2 A
39.
a.
b.
Exam Review Answers
Since the equations are mathematically equivalent, there is an infinite
number of solutions.
The solutions include all of the coordinate pairs along the line.
y
x
40.
41.
a.
Since the lines have the same slope and different y-intercepts, they are
parallel and there are no solutions.
b.
The lines are parallel, therefore, there are no points that satisfy both
equations, and thus there are no solutions.
a.
y  7000  1250 x
b.
7000. It is the sign-on bonus Victor receives before he begins to work at
Computer Industries.
c.
1250 dollars per week. Victor would earn $1250 per week at Computer
Industries.
d.
y  1600 x
e.
0. Victor does not receive any money from Ideal Imaging before he
begins to work.
f.
1600 dollars per week. Victor would earn $1600 per week at Ideal
Imaging.
g.
 y  7000  1250 x

 y  1600 x
h.
x  20 , y  32000
i.
After 20 weeks, Victor would have earned about $32,000 whether he
worked at Computer Industries or Ideal Imaging. Before this point, his
total earnings would have been more at Computer Industries. After this
point, his total earnings would be more at Ideal Imaging.
MCPS © 2015–2016
Bridge to Algebra 2 A
42.
Exam Review Answers
a.
15 x  25 y  110

x  y  6
b.
15 25  x  110 
 1 1  y    6 

   
c.
x  4, y  2
d.
D’Quell jogged 4 miles and walked 2 miles.
Cost
a.
$1074.00 
Sweats  $887.80 
b.
$1961.80
44.
a.
b.
c.
d.
Graph III
Graph I
Graph II
Graph IV
45.
a.
2400 x  400 y  20, 000

 x  y  20
b.
see graph below.
T's
Number of printers
43.
Number of computers
c.
Sample responses include:
5 computers and 25 printers
17 computers and 7 printers
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10 computers and 15 printers
20 computers and 5 printers
22 computers and 0 printers
Bridge to Algebra 2 A
46.
Exam Review Answers
2 x , if 1  x  5
f  x  
10  1 x  5  , if x  6
47.
D
48.
a.
6 8
10 12 


The dimensions are 2  2 .
b.
6 8
10 12 


The dimensions are 2  2 .
c.
They are identical. The dimensions of both matrices are 2  2 .
a.
 4 4 
 4 4 


The dimensions are 2  2 .
b.
4 4
4 4


The dimensions are 2  2 .
c.
They are additive inverses. The dimensions of both matrices are 2  2 .
a.
19 22 
 43 50 


The dimensions are 2  2 .
b.
 23 34 
 31 46 


The dimensions are 2  2 .
49.
50.
51.
c.
Multiplication is not commutative with these matrices.
Both matrices are 2  2 .
a.
2
 2 1 
1 
3
 or  2
1



 
1.5 0.5
2
2
b.
c.
1 0 
0 1 


d.
1 0 
0 1 


e.
Multiplying a matrix by its inverse matrix is commutative and results in
the identity matrix.
MCPS © 2015–2016
Bridge to Algebra 2 A
52.
53.
54.
Exam Review Answers
a.
23
b.
23
c.
The product is not possible.
d.
2 1
a.
 14 15 3 
11.5 11.5 .5


b.
 31 
 27.5


The dimensions are 2  3 .
The dimensions are 2 1 .
The product matrix CE has dimensions 2  5 .
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