Math Homework Help Service
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Transcript of Math Homework Help Service
Math Homework Help Service
Tutorhelpdesk David Luke
Contact Us:
Phone: (617) 807 0926
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Email: - [email protected]
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About Math Homework: At Tutorhelpdesk we offer efficient
and cost effective math homework help service for students
looking for quality math study support for completing their
math homework projects. Students need to send their
homework task to us and once the initial payment formality
etc. will be completed we assign one of our best math tutors to
undertake the project for due completion. We only appoint
tutors with comprehensive math background for doing math
homework services. We also offer free of cost modification
service and online solution clarification session between the
related students and the working tutor. At Tutorhelpdesk.com we value your time line and
your privacy while offering you math assignment help.
Sample of Math Homework Illustrations and Solutions:
Question 1: The side of a square exceeds the side of the another square by 4 cm and the
sum of the areas of the two squares is 400 sq. cm. Find the dimensions of the squares.
Solution. Set 𝑆1 and 𝑆2 be two squares. Let the side of the square 𝑆2 be x cm in length.
Then, the side of square S1 is (x + 4) cm.
∴ Area of square 𝑆1 = 𝑥 + 4 2
And, Area of square 𝑆2 = 𝑥2
It is given that
Area of square 𝑆1 + Area of square 𝑆2 = 400 cm2
= 𝑥 + 4 2 + 𝑥2 = 400 = (𝑥2 + 8x + 16) + x = 400 = 2𝑥2 + 8x – 384 = 0 = 𝑥2 + 4x – 192 =
0
= 𝑥2 + 16x – 12x – 192 = 0 =x(x + 16) -12 (x + 16) = 0 = (x + 16) (x – 12) = 0 x = 12 or
x = -16
Since the length of the side of a square cannot be negative: x = 12
∴ Side the length of the side of a square cannot be negative: x = 12
∴ Side of square 𝑆1 = x + 4 = 12 + 4 = 16 cm and Side of square 𝑆2 = 12 cm.
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Question 2:
There is square field whose side is 44 m. A square flower bed is prepared in its centre
leaving gravel path all round the flower bed and gravelling the path at $ 2.75 and $ 1.50
per square meter respectively is $ 4904. Find the width of the gravel path.
Solution. Let the width of the gravel path be x meters. Then, Each side of the square
flower bed is (44 – 2x) meters.
Now area of the square field = 44 × 44 = 1936 m2
Area of the flower bed = (44 - 2𝑥)2 m2
∴ Area of the gravel path
= Area of the field – Area of the flower bed
= 1936 – (44 - 2𝑥)2
= 1936 – (1936 – 176x + 4𝑥2) m2
Cost of laying the flower bed
= (Area of the flower bed) (Rate per sq. m)
= (44 - 2𝑥)2 × 275
100 =
11
4 (44 - 2𝑥)2 = 11 ( 22 – 𝑥)2
Cost of gravelling the path = (Area of the path) × (Rate per sq. m) = (176x - 4𝑥2) 150
100 =
6(44x - 𝑥2)
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It is given that the total cost of laying the flower bed and gravelling the path is $ 4904.
∴ 11 (22 – 𝑥)2 + 6 (44x - 𝑥2) = 4904 = 11(484 – 44x + 𝑥2) + (364x - 6𝑥2) = 4904.
= 5𝑥2 - 220x + 5324 = 4908 = 5𝑥2 – 220x + 420 = 0 = 𝑥2 -44x + 84 = 0
= x2 – 42x – 2x + 84 = 0 = x(x – 42) -2(x – 42) = 0
= (x -2) (x – 42) = 0 = x = 2 or x = 42.
But, x ≠ 42, as the side of the square is 44m. Therefore, x = 2.
Hence, the width of the gravel path is 2 meters.
Question 3:
A chess board contains 64 equal squares and the area of each square is 6.25 cm2. A border
round the board is 2 cm wide. Find the length of the side of the chess board.
Solution. Let length of the side of the chess board be x cm. Then Area of 64 squares =
𝑥 − 4 2
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∴ 𝑥 − 4 2 = 64 × 6.25 = 𝑥2 - 8x + 16 = 400
= 𝑥2 – 8x – 384 = 0 = 𝑥2 - 24x + 16x – 384 = 0
= (x – 24) (x + 16) = 0 = x = 24 cm
Question 4:
A swimming pool is filled with three pipes with uniforms flow. The first tow pipes operating
simultaneously, fill the pool in the same time during which the pool is filled by the third pipe
alone. The second pipe fills the pool five hours faster than the first pipe and four hours
slower than the third pipe. Find the time required by each pipe to fill the pool separately.
Solution. Let v be the volume of the pool and x the number of hours required by the
second pipe alone to fill the pool. Then, first pipe takes (x + 5) hours, while the third pipe
takes (x -4) hours to fill the pool. So, the parts of the pool filled by the first, second and
third pipes in one hour are respectively
V
x+5, V
x and
V
x−4
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Let the time taken by the first and second pipes fill the pool simultaneously be 6 hours.
Then, the third pipe also takes the same time to fill the pool.
∴ V
x+5,V
x t =
𝑉
𝑥−4t =
1
𝑥+5 +
1
𝑥 =
1
𝑥−4
= (2x + 5) (x – 4) = 𝑥2 + 5x = 𝑥2 - 8x- 20 = 0
= 𝑥2 - 10x + 2x – 20 = 0 = (x – 10) (x + 2) = 0 = 10 or x = -2
But, x cannot be negative, So, x = 10.
Hence, the timings required by first, second and third pipes to fill the pool individually are
15 hours, 10 hours respectively.