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The trick ski requires 6 labor hours for fabricating and 1 labor hour for finishing. The slalom ski requires 4 labor hours for fabricating and 1 labor hour for finishing. The maximum labor hours available per day for fabricating and finishing are 108 and 24, respectively. If X is the number of trick skis and Y is the number of slalom skis produced per day, write a system of linear inequalities that indicates appropriate restraints on X and Y. Find the set of feasible solutions graphically for the number of each type of ski that can be produced.
Please help me with this, I am totally lost. Please expalin the steps so I'll understand how to solve these problems.
1 solutions
Answer 461712 by ankor@dixie-net.com(15745)   on 2013-06-17 21:47:48 (Show Source):
You can put this solution on YOUR website!company makes two types of water skis, a trick ski and a slalom ski.
The trick ski requires 6 labor hours for fabricating and 1 labor
hour for finishing.
The slalom ski requires 4 labor hours for fabricating and 1 labor
hour for finishing.
The maximum labor hours available per day for fabricating and
finishing are 108 and 24, respectively.
If X is the number of trick skis and Y is the number of slalom skis
produced per day, write a system of linear inequalities that
indicates appropriate restraints on X and Y.
Find the set of feasible solutions graphically for the number of each type of ski that can be produced.
:
Fabricating equation
6x + 4y <= 108
:
Finishing equation
1x + 1y <= 24
:
since you can make negatives skis
x => 0
y => 0
:
Find the set of feasible solutions graphically for the number of each
type of ski that can be produced.
We have to put the equations into the slope/intercept to graph
6x + 4y = 108
4y = -6x + 108
divide by 4
y = -1.5x + 27; Red
and
x + y = 24
y = -x + 24; Green
Graph these two equations
The feasibility region is at or below the area bounded by the points
x=0, y=24; x=6, y=18; x=18; y=0
:
you can prove this to yourself using the fabricating equation
6x + 4y <= 108
x=6 trick skies, y=18 salom skies
6(6) + 4(18) =
36 + 72 = 108 total hrs
|
Travel_Word_Problems/758663: Can You Please Help?
Here is the question---
A man walked 12km at a certain rate and then 6km farther at a rate of 1 and a half km/hour faster. If he had walked the whole distance at the faster rate, his time would have been 20 minutes less. How long did it really take him to walk the 18km?
Thank You for Your Time :D
1 solutions
Answer 461638 by ankor@dixie-net.com(15745) on 2013-06-17 11:06:41 (Show Source):
You can put this solution on YOUR website!A man walked 12km at a certain rate and then 6km farther at a rate of
1 and a half km/hour faster.
If he had walked the whole distance at the faster rate,
his time would have been 20 minutes less.
How long did it really take him to walk the 18km?
:
let r = "a certain rate"
then
(r+1.5) = the faster rate
:
Change 20 min to  hr
:
Actual time - faster time = 20 min
 +  -  =
Subtract like terms
-  =
multiply by 3r(r+1.5)
3(r+1.5)(12) - 3r(12) = r(r+1.5)
(3r + 4.5)(12) - 36r = r^2 + 1.5r
36r + 54 - 36r = r^2 + 1.5r
0 = r^2 + 1.5r - 54
Use the quadratic formula to find r
You can do the math, I got a positive value: r = 6.6366 km/hr
:
Find the time:
t(r) =  + 
t(r) = 1.8 + .74
t(r) = 2.545 hrs
:
:
You can check this by finding the time at the faster rate
 Should be .333 hrs less
|
Travel_Word_Problems/758580: The sanderling is a small shorebird about 6.5 in. long, with a thin, dark bill and a wide, white wing stripe. If a sanderling can fly 30 mi with the wind in the same time it can fly 18 mi against the wind when the wind speed is 8 mph, what is the speed of the bird in still air?
1 solutions
Answer 461580 by ankor@dixie-net.com(15745) on 2013-06-16 21:46:01 (Show Source):
You can put this solution on YOUR website! If a sanderling can fly 30 mi with the wind in the same time it can
fly 18 mi against the wind when the wind speed is 8 mph,
what is the speed of the bird in still air?
:
Let s = bird speed in still air
then
(s+8) = ground speed of the bird with the wind
and
(s-8) = ground speed against the wind
:
Write a time equation; time = dist/speed
:
 = 
cross multiply
30(s-8) = 18(s+8)
30s - 240 = 18s + 144
30s - 18s = 144 + 240
12s = 384
s = 384/12
s = 32 mph is the speed in still air
:
:
Check this by finding the time of each way, should be equal
With: 30/40 = .75 hrs
Against: 18/24 = .75 hrs
|
Reduction-of-unit-multipliers/758473: a rectangular lot with a dimension of 5m by 8m is to be fenced and tiled. determine the perimeter fence in terms of yard and number of tiles needed if the owner prefers an 8 in by 8 in tile. i really need your help. please
1 solutions
Answer 461486 by ankor@dixie-net.com(15745) on 2013-06-16 07:44:15 (Show Source):
You can put this solution on YOUR website!a rectangular lot with a dimension of 5m by 8m is to be fenced
and tiled.
determine the perimeter fence in terms of yard and number of tiles needed if the owner prefers an 8 in by 8 in tile.
:
Convert to yards:
1.094 * 5 = 5.47
1.094 * 8 = 8.752
then
2(5.47) * 2(8.752) = 28.444 yds is the perimeter, (28 yds 16 inches)
:
Find the area in square inches
5.47 * 8.752 * 36 * 36 = 62044 sq/inches
:
Each tile is 8*8 = 64 sq/inches
therefore
62044/64 = approx 970 tiles required
|
Word_Problems_With_Coins/758336: a student has 55 coins worth a total of $7.35. each coin is either a nickel or a quarter. of x is the number of nickels, then x can be determined for the equation
1 solutions
Answer 461472 by ankor@dixie-net.com(15745) on 2013-06-15 21:53:56 (Show Source):
You can put this solution on YOUR website!a student has 55 coins worth a total of $7.35.
each coin is either a nickel or a quarter.
If x is the number of nickels, then x can be determined for the equation
:
Let x = no. of nickels
total coins is 55, therefore
(55-x) = no. quarters
:
.05x + .25(55-x) = 7.35
.05x + 13.75 - .25x = 7.35
.05x - .25x = 7.35 - 13.75
-.20x = -6.40
x = -6.4/-.2
x = +32 nickels
:
:
See if this checks out: 55-32 = 23 quarters
.05(32) = 1.60
.25(23) = 5.75
-----------------
total$ = 7.35
|
Quadratic-relations-and-conic-sections/758377: A bridge is built in the shape of a parabolic arch. The bridge arch has a span of 196 feet and a maximum height of 30 feet. Find the height of the arch at 15 feet from its center.
1 solutions
Answer 461462 by ankor@dixie-net.com(15745) on 2013-06-15 21:09:54 (Show Source):
You can put this solution on YOUR website!A bridge is built in the shape of a parabolic arch.
The bridge arch has a span of 196 feet and a maximum height of 30 feet.
Find the height of the arch at 15 feet from its center.
:
Let the left side of the arch be at origin (0,0) then axis of symmetry
and max will be at x=98, y=30 and the right side: x=196,y=0
Using the form ax^2 + bx + c = y; c=0 so we can ignore that
x=98, y= 30
98^2a + 98b = 30
9604a + 98b = 30
and
x=196, y=0
196^2a + 196b = 0
38416a + 196b = 0
:
Multiply the 1st equation by 2, subtract from the above equation
38416a + 196b = 0
19208a + 196b = 60
-------------------subtraction eliminate b, find a
19208a = -60
a = -60/19208
a = -.0031237
:
Find b using the 1st equation
9604(-.0031237) + 98b = 30
-30 + 98b = 30
98b = 30 + 30
98b = 60
b = 60/98
b = .612
:
The equation for the arch: y = -.0031237x^2 + .612x
:
Graphically
:
Find the height of the arch at 15 feet from its center. (Green line)
You can do this replace x with 83 and find y (height)
Do the same with x = 113
|
Linear-equations/758341: I have an algebra problem. What it is is a letter from a basic math student and I need to come up with the equation and the answer then be able to explain it to them in a simple way they can understand.
Here is the basic math students question.. During his shift at the school carnival he sold 112 drinks. He thought he only needed to keep track of the total amount of drinks sold, but it turns out they want to know how many bottles of water and how many bottles of soda were sold as separate numbers. The question is: If the number of bottles of water sold was 4 less than 3 times the number of bottles of soda, how many of each did he sell ?
I have to figure out the answer ( how many water and how many sodas) explain how i set up the equation and solved it. So in case the situation happens again they could answer the question.
1 solutions
Answer 461439 by ankor@dixie-net.com(15745) on 2013-06-15 17:23:21 (Show Source):
You can put this solution on YOUR website!During his shift at the school carnival he sold 112 drinks.
He thought he only needed to keep track of the total amount of drinks
sold, but it turns out they want to know how many bottles of water
and how many bottles of soda were sold as separate numbers.
The question is: If the number of bottles of water sold was 4 less
than 3 times the number of bottles of soda, how many of each did he sell?
:
Let w = no. of bottles of water sold
Let s = no. of bottles of soda
:
Total sold equation
w + s = 112
w = (112-s); use this for substitution
:
"the number of bottles of water sold was 4 less
than 3 times the number of bottles of soda,"
w = 3s - 4
A big mistake here. Let me correct this
Replace w with (112-s)
112-s = 3s - 4
112 + 4 = 3s + s
116 = 4s
s = 116/4
s = 29 sodas
then
w = 112 - 29
w = 83 waters sold
:
See if that checks out in the statement:
"the number of bottles of water sold was 4 less
than 3 times the number of bottles of soda,
83 = 3(29) - 4
83 = 87 - 4
|
Geometry_Word_Problems/758127: twice the first angle is 20 deg less than the third, 1/2 of the third is 60 deg less than the sum of the 1st and 2nd angles.find the angles
1 solutions
Answer 461428 by ankor@dixie-net.com(15745) on 2013-06-15 16:55:42 (Show Source):
You can put this solution on YOUR website!Three angles, A,B,C;
Just write an equation for what it says.
:
twice the first angle is 20 deg less than the third,
2A = C-20
or
C = 2A+20
:
1/2 of the third is 60 deg less than the sum of the 1st and 2nd angles.
.5C = A + B - 60
multiply both sides by 2
C = 2A + 2B - 120
therefore
2A+20 = A + B - 60
2A - A = B - 60 - 20
A = B-80
or
B = A+80
:
And assuming this is a triangle
A + B + C = 180
replace B with (A+80); replace C with (2A+20)
A + A+80) + 2a+20 = 180
4A + 100 = 180
4A = 180 - 100
4A = 80
Divide both sides by 4
A = 20 degrees
then
B = 20 + 80
B = 100 degrees
and
C = 2(20)+20
C = 60 degrees
:
20 + 100 + 60 = 180; confirms our solutions
|
Linear_Equations_And_Systems_Word_Problems/758328: A number consists of two digits. The digit in the unit's place is less than the digit in the ten's place by 2. If the number is subtracted from 11times the sum of the digits then the digits are reversed. Find the number.
1 solutions
Answer 461422 by ankor@dixie-net.com(15745) on 2013-06-15 16:27:02 (Show Source):
You can put this solution on YOUR website!A number consists of two digits.
10a + b
:
The digit in the unit's place is less than the digit in the ten's
place by 2.
b = a-2
:
If the number is subtracted from 11 times the sum of the digits, then
the digits are reversed.
11(a+b) - (10a+b) = 10b + a
11a + 11b - 10a - b = 10b + a
combine the like terms on the left
11a - 10a - a + 11b - b - 10b = 0
and you get 0! So that's not very helpful, just choose a number
97 is good one
11(9+7) - 97 = 79
or how about 64
11(6+4) - 64 = 46
or 75
11(7+5) - 75 = 57
Take your pick
|
Age_Word_Problems/758092: the sum of the ages of the parents and the three children is decades over a century.
The father is twice as old as the eldest child.
When the eldest child was born, the sum of the parents age is 54.
When the youngest child was born, the sum of the parents age was 70.
In 38 years, the sum of the parents ages will be equal to the sum of the childrens ages.
How old is the second child?
1 solutions
Answer 461316 by ankor@dixie-net.com(15745) on 2013-06-14 21:29:18 (Show Source):
You can put this solution on YOUR website!the sum of the ages of the parents and the three children is decades
over a century.
:
f, m, a, b, c; (a is the oldest child)
The father is twice as old as the eldest child.
f = 2a
:
When the eldest child was born, the sum of the parents age is 54.
(f-a) + (m-a) = 54,
f + m - 2a = 54
we know that f = 2a
2a + m - 2a = 54
m = 54 is mom's age
:
When the youngest child was born, the sum of the parents age was 70.
(f-c) + (m-c) = 70,
f + m - 2c = 70
:
Use elimination with these two equations
f + m - 2c = 70
f + m - 2a = 54
---------------subtraction eliminates f and m
+2a - 2c = 16
simplify
a - c = 8
or
c = a - 8
:
In 38 years, the sum of the parents ages will be equal to the sum
of the children's ages.
(f+38) + (m+38) = (a+38) + (b+38) + (c+38)
combine the values
f + m + 76 = a + b + c + 114
subtract 76 from both sides
f + m = a + b + c + 38
Replace f with 2a
2a + m = a + b + c + 38
subtract a from both sides and we have
a + m = b + c + 38
replace c with (a-8)
a + m = b + a - 8 + 38
subtract a from both sides
m = b + 30
We know that mom is 54
54 = b + 30
b = 54 - 30
b = 24 is the 2nd child's age
:
:
:
Check this mess out by assuming the total of their present ages is
an even 10 (a decade) over 100 and a=30
f = 60 (2a)
m = 54
a = 30
b = 24 (m-30)
c = 22 (a-8)
-------
tot: 190
|
Travel_Word_Problems/758091: A car traveling at 70 kilometers per hour is passed by a second car going in the same direction at a constant speed. After 30 seconds, the two cars are 500 meters apart. Find the speed of the second car.
1 solutions
Answer 461266 by ankor@dixie-net.com(15745) on 2013-06-14 15:35:06 (Show Source):
You can put this solution on YOUR website!A car traveling at 70 kilometers per hour is passed by a second car
going in the same direction at a constant speed.
After 30 seconds, the two cars are 500 meters apart.
Find the speed of the second car.
:
let s = speed of the passing car
:
We're working km/hr:
change 500 m to  km
change 30 sec to  hrs
:
Write a distance equation; dist = speed * time
:
Passing car dist - 70 km/hr car dist = 500 meters
s - (70) =
multiply eq by 120 to cancel the denominators, results:
1s - 1(70) = 120*
s - 70 = 60
s = 60 + 70
s = 130 km/hr speed of the passing car
;
:
Confirm this by finding the distance each car traveled
*130 = 1.08 km
* 70 = .58 km
-------------------------
difference in dist: .5 km which is 500 m
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Travel_Word_Problems/758088: The cruising speed of an airlines is 150 miles per hour (relative to the ground). you wish to hire the plane for 3 hour sightseeing trip. You instruct the pilot to fly north as far as he can and still return to the airport at the end of the allotted time. how far north should the pilot fly if the wind is blowing far from the north at 30 miles per hour.
1 solutions
Answer 461265 by ankor@dixie-net.com(15745) on 2013-06-14 14:01:53 (Show Source):
You can put this solution on YOUR website!The cruising speed of an airlines is 150 miles per hour (relative to
the ground).
you wish to hire the plane for 3 hour sightseeing trip.
You instruct the pilot to fly north as far as he can and still return
to the airport at the end of the allotted time.
how far north should the pilot fly if the wind is blowing from
the north at 30 miles per hour.
:
Let d = one way distance to point of return
we know
150 - 30 = 120 mph, ground speed going north
and
150 + 30 = 180 mph, ground speed going south
:
Write a time equation; time = dist/speed
:
time north + time back = 3 hrs
 +  = 3
multiply by 360 to cancel the denominators, results:
3d + 3d = 360(3)
5d = 1080
d = 1080/5
d = 216 miles to return point
;
:
Check this by finding the actual times:
216/120 = 1.8 hrs
216/180 = 1.2 hrs
------------------
total time: 3 hrs
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Miscellaneous_Word_Problems/758061: The ratio of the weight of an object on Mars to the weight of an object on Earth is 0.4 to 1.
A- How much will a 7 ton rocket weigh on Mars?
B- How much will a 132 lb astronaut weigh on Mars?
A: A 7 ton rocket will weigh ____ ton on Mars. (round to the nearest tenth)
1 solutions
Answer 461209 by ankor@dixie-net.com(15745) on 2013-06-13 21:57:47 (Show Source):
You can put this solution on YOUR website!The ratio of the weight of an object on Mars to the weight of an
object on Earth is 0.4 to 1.
A- How much will a 7 ton rocket weigh on Mars?
 = 
Cross multiply
r = .4(7)
r = 2.8 tons on Mars
:
B- How much will a 132 lb astronaut weigh on Mars?
 =
a = 132 * .4
a = 52.8 lb
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Rate-of-work-word-problems/758019: Tina can completely weed her vegetable garden in 1hr and 30 min. Her friend marisa can do the same in 2 hrs. if they worked together, how long would it take?
I'm not sure what steps to go about using to complete this. I thought it might be done by using a system of equations but I think I would need more information in order to solve that.
1 solutions
Answer 461187 by ankor@dixie-net.com(15745) on 2013-06-13 20:00:47 (Show Source):
You can put this solution on YOUR website!Tina can completely weed her vegetable garden in 1hr and 30 min.
Her friend marisa can do the same in 2 hrs.
if they worked together, how long would it take?
:
Let t = the time required when working together (in hrs)
Let the completed job = 1
:
Each will do a fraction of the job, the two fractions add up to 1
:
 +  = 1
multiply by 6 to get rid of the denominators, results
4t + 3t = 6
7t = 6
t = 6/7 hrs, or converted to minutes: 6/7 * 60 = 51.4 minutes
:
:
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Bodies-in-space/757981: Suppose three spherical balls of wax with radius r are packed in a cylinder also with radius r and the balls are melted down. To what depth will the cylinder be filled. The answer needs to be in terms of r. I am totally stumped. Thank you
1 solutions
Answer 461184 by ankor@dixie-net.com(15745) on 2013-06-13 19:41:45 (Show Source):
You can put this solution on YOUR website!Suppose three spherical balls of wax with radius r are packed in
a cylinder also with radius r and the balls are melted down.
To what depth will the cylinder be filled.
The answer needs to be in terms of r.
:
Find the vol of the three balls in terms of r
V(r) = 3 *  * 
Cancel the 3
V(r) =  cu/units is the volume of the wax
:
let d = the depth of the wax in the cylinder when melted
 =
divide both sides by 
d = 4r units is the depth
|
test/757661: A and B are two cars . they start to move with constant speed from the same spot at the same time . car A moves toward the east with speed 8 km/h . car B moves toward north with speed Vb . after 2 hours the distance between the two cars is 200 km . find Vb ?!
1 solutions
Answer 461051 by ankor@dixie-net.com(15745) on 2013-06-12 20:50:01 (Show Source):
You can put this solution on YOUR website!A and B are two cars .
they start to move with constant speed from the same spot at the
same time .
car A moves toward the east with speed 8 km/h .
car B moves toward north with speed Vb .
after 2 hours the distance between the two cars is 200 km .
find Vb ?!
:
Dist = speed * time
2(8) = 16 km traveled by Car A
2Vb km traveled by car B
:
The is a pythag type problem; a^2 + b^2 = c^2, where:
a = 16
b = 2Vb
c = 200
therefore:
16^2 + (2Vb)^2 = 200^2
256 + 4Vb^2 = 40000
4Vb^2 = 40000 - 256
4Vb^2 = 39744
Vb^2 = 39744/4
Vb^2 = 9936
Vb = 
Vb = 99.68 km/hr
;
:
I'll let you check this: Car B travels 2*99.68 = 199.36 km
Use your calc enter: 
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Travel_Word_Problems/757518: A 500 yard long train, travelling at 90 mph, enters a three mile long tunnel. How many seconds will elapse between the movement the front of the train enters the tunnel and the moment the end of the train clears the tunnel?
1 solutions
Answer 461033 by ankor@dixie-net.com(15745) on 2013-06-12 20:02:25 (Show Source):
You can put this solution on YOUR website!A 500 yard long train, travelling at 90 mph, enters a three mile
long tunnel.
How many seconds will elapse between the movement the front of the
train enters the tunnel and the moment the end of the train clears
the tunnel?
:
Convert 500 yds to miles:  = .284 mi
:
 * 3600 = 131.36 seconds
|
Travel_Word_Problems/757322: Ron and pat leaves for the beach at the same point. Ron leaves first pat leaves 45 mins later traveling 10 mph faster then Ron. pat passes ron 4 hours later. find the rate of each driver.
1 solutions
Answer 461027 by ankor@dixie-net.com(15745) on 2013-06-12 19:51:49 (Show Source):
You can put this solution on YOUR website!Ron and pat leaves for the beach at the same point.
Ron leaves first, Pat leaves 45 mins later traveling 10 mph faster
than Ron.
Pat passes Ron 4 hours later. find the rate of each driver.
:
Since we a dealing in hrs here, convert 45 min to .75 hrs
:
From the information given, we know
P's travel time = 4 hrs
R's travel time = 4.75 hrs
:
let s = R's rate
then
(s+10) = P's rate
:
When P catches R, they will have traveled the same distance.
Write a distance equation; Dist = time * speed
:
R's dist = P's dist
4.75s = 4(s+10)
4.75s = 4s + 40
4.75s - 4s = 40
.75s = 40
s = 40/.75
s = 53 mph is R's rate
then
53 + 10 = 63 mph is P's rate
:
:
You can check this out for yourself, determine the distance each
traveled, should be the same. (dist = rate * time)
|
Travel_Word_Problems/757565: A started walking in north at 7 am with the speed of 5 km/hr. after one hour B started towards east on a cycle with the speed of 16 km/hr. at what time the distance between them will be 52 km?
1 solutions
Answer 460978 by ankor@dixie-net.com(15745) on 2013-06-12 17:11:17 (Show Source):
You can put this solution on YOUR website!A started walking in north at 7 am with the speed of 5 km/hr.
after one hour B started towards east on a cycle with the speed
of 16 km/hr.
at what time the distance between them will be 52 km?
:
Let t = travel time of the bike
then
(t+1) = walking time
:
dist = speed * time
:
This is a pythag problem: a^2 + b^2 = c^2, where
a = 16t, bike dist
b = 5(t+1), walking dist
c = 52, dist apart in t hrs from 8 AM
:
(16t)^2 + (5(t+1)^2 = 52^2
256t^2 + (5t+5)^2 = 2704
256t^2 + 25t^2 + 50t + 25 = 2704
281t^2 + 50t + 25 - 2704 = 0
281t^2 + 50t - 2679 = 0
solve this equation using the quadratic formula
Positive solution t = 3 hrs
At 11 AM they will be 52 km apart
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Permutations/757600: Two persons are to run a race, but one can run 11 meters per second, whereas the other can run 7 meters per second. If the slower runner has a 42-meter head start, how long will it be before the faster runner catches the slower runner, if they begin at the same time?
1 solutions
Answer 460947 by ankor@dixie-net.com(15745) on 2013-06-12 14:25:38 (Show Source):
You can put this solution on YOUR website!Two persons are to run a race, but one can run 11 meters per second,
whereas the other can run 7 meters per second.
If the slower runner has a 42-meter head start, how long will it be
before the faster runner catches the slower runner, if they begin
at the same time?
:
We can us relative speed here which is 11 - 7 = 4 m/sec
How long would it take to cover 42 meters at this speed
:
 = 10.5 sec
:
:
You can confirm this for yourself, find the distance traveded
10.5 * 11 = 115.5 m
10.5 * 7 = 73.5 m
--------------------
the difference: 42 m
|
Linear_Equations_And_Systems_Word_Problems/757539: A couple of girls go for a horse race clockwise around the outside of a rectangular field.
The rectangular field has 'a' as the shortest side and 'b' as the long side of a rectangle.
Mary runs all around the field for a total of 20km. Annabelle only gets half way along the first side marked with 'b' before cutting straight across the field, before heading back to the start. She in total rides for 16 km. What are the dimensions of the field?
1 solutions
Answer 460889 by ankor@dixie-net.com(15745) on 2013-06-12 08:24:59 (Show Source):
You can put this solution on YOUR website!A horse race clockwise around the outside of a rectangular field.
The rectangular field has 'a' as the shortest side and 'b' as the long
side of a rectangle.
Mary runs all around the field for a total of 20km. Annabelle only
gets half way along the first side marked with 'b' before cutting
straight across the field, before heading back to the start.
She in total rides for 16 km. What are the dimensions of the field?
:
Mary's perimeter
2a + 2b = 20
Simplify, divide by 2
a + b = 10
:
Anna's perimeter
2a + 2(.5b) = 16
simplify, divide by 2
a + .5b = 8
:
Using eliminatation
a + b = 10
a +.5b = 8
------------ subtracting eliminates a, find b
0 + .5b = 2
b = 4; (multiplied by 2)
then
a + 4 = 10
a = 6; (subtracted 4 from both sides)
:
4 by 6 is the dimensions
|
Exponents/757358: what is x to the seventh power divided by x to the negative second power? The book says the answer is x to the ninth power but how?
1 solutions
Answer 460811 by ankor@dixie-net.com(15745) on 2013-06-11 21:22:23 (Show Source):
You can put this solution on YOUR website!what is x to the seventh power divided by x to the negative second power? The book says the answer is x to the ninth power but how?
:
remember you can get rid of the negative exponent by writing the
reciprocal, therefore
 *  or just 
add exponents when you multiply
|
Systems-of-equations/757264: Which of these images represents the following system of equations being solved graphically?
-2x + 2y = 8
-4x - 6y = -4
1 solutions
Answer 460763 by ankor@dixie-net.com(15745) on 2013-06-11 16:29:50 (Show Source):
You can put this solution on YOUR website!Which of these images represents the following system of equations
being solved graphically?
:
Put both equations into the slope/intercept form
-2x + 2y = 8
2y = 2x + 8
Divide by 2
y = x + 4, the first equation
and
-4x - 6y = -4
-6y = 4x - 4
divide -6
y = -  x +
reduce fractions
y = -  x +
:
Plot these two equations
solution: -2, 2
|
Money_Word_Problems/757291: I am offered a job that pays $12/hr for 40 hrs a week. I want to rent an apartment with two other friends that requires a year-long lease. Bills and expenses will cost me $300 per month. I am also making monthly payments on a car in the amount of $1, 521. If I accept the job, what is the maximum rent I can pay for the apartment?
1 solutions
Answer 460760 by ankor@dixie-net.com(15745) on 2013-06-11 15:24:16 (Show Source):
You can put this solution on YOUR website!I am offered a job that pays $12/hr for 40 hrs a week.
I want to rent an apartment with two other friends that requires a year-long lease.
Bills and expenses will cost me $300 per month.
I am also making monthly payments on a car in the amount of $1, 521.
If I accept the job, what is the maximum rent I can pay for the apartment?
:
(40*4*12) - 300 - 1521 = $99 for rent
|
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