9th Standard Syllabus & Materials
9th Standard
TN 9th Tamil உள்ளத்தின் சீர் -கற்கண்டு (இலக்கணம்) - தொடர் இலக்கணம், ஆகுபெயர் Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil உள்ளத்தின் சீர் -விரிவானம் (துணைப்பாடம்) - தாய்மைக்கு வறட்சி இல்லை! Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil உள்ளத்தின் சீர் -கவிதை பேழை (செய்யுள்) - மார்கழி பெருவிழா Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil உயிருக்கு வேர்-இலக்கணம் - பகுபத உறுப்பிலக்கணம் Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil அமுதென்று பேர் - இலக்கணம்-எழுத்து -அளபெடை Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil அமுதென்று பேர்-துணைப்பாடம் - ஆறாம்திணை Important Questions And Answers Study Material - QB365 Set A

Published on: 07/08/2019
Download Tamil Nadu 9th Standard Maths question papers, model tests, one-mark questions, important questions, and public exam papers in PDF format. Free study materials and answer keys for TN State Board students.
Questions + Answers key
Take MCQ Maths Test1.
Construct ΔABC with AB = 5 cm ㄥB = 1000 and BC = 6 cm. Also locate its circumcentre draw circumcircle.
2.
Classify the numbers as rational or irrational
(i) \(\sqrt { 10 } \)
(ii) \(\sqrt { 49 } \)
(iii) 0.025
(iv) \(0.7\overline { 6 } \)
(v) 2.505500555...
(vi) \(\frac { \sqrt { 2 } }{ 2 } \)
3.
A and B are two sets such that n(A – B) = 32 + x, n(B – A) = 5x and n(A∩B) = x. Illustrate the information by means of a Venn diagram. Given that n(A) = n(B), calculate the value of x.
4.
In a village of 100 families, 65 families buy Tamil newspapers and 55 families buy English newspapers. Find the number of families who buy
(i) Both Tamil and English newspapers.
(ii) Tamil newspapers only
(iii) English newspapers only.
5.
Classify the following polynomials.
| S.No | Polynomial | Based on number of terms | Based on their degree |
|---|---|---|---|
| 1 | \(\frac { { x }^{ 2 } }{ \sqrt { 2 } } +x+1\) | ||
| 2 | \(\sqrt { 5 } { x }^{ 2 }-\frac { 6 }{ 5 } x\) | ||
| 3 | 1 | ||
| 4 | \({ m }^{ 4 }-\frac { 6 }{ 7 } { m }^{ 2 }-6m+2.7\) | ||
| 5 | \(\frac { { t }^{ 3 } }{ \sqrt { 6 } } +\frac { { t }^{ 4 } }{ 4 } -t \) |
6.
Express\(\frac { 1 }{ 13 } \) in decimal form. Find the length of the period of decimals
7.
The length of a rectangle is (3x+2) units and it’s breadth is (3x–2) units. Find its area in terms of x. What will be the area if x = 20 units.
8.
In a parallelogram ABCD, the bisectors of the consecutive angles ∠A and ∠B intersect at P. Show that ∠APB = 90o.

9.
Find any two irrational numbers between\(\frac { 6 }{ 7 } \) and \(\frac { 12 }{ 13 } \)
10.
Show that the points A(7,10), B(-2, 5), C(3, -4) are the vertices of a right angled triangle.
1.
Steps for construction:
Step 1: Draw the ΔABC with the given measures.
Step 2: Construct the perpendicular bisector of any two sides (AB and BC) and let them meet at S which is the circumcenter.
Step 3: With S as centre and SA = SB = SC as radius draw the circumcircle to passes through A, Band C.


Circum radius = 4.3 cm.
2.
(i) \(\sqrt { 10 } \) is an irrational number ( since 10 is not a perfect square number).
(ii) \(\sqrt { 49 } =7=\frac { 7 }{ 1 } \) a rational number(since 49 is a perfect square number).
(iii) 0.025 is a rational number (since it is a terminating decimal).
(iv) \(0.7\overline { 6 } \) = 0.7666…. is a rational number ( since it is a non – terminating and recurring decimal expansion).
(v) 2.505500555…. is an irrational number (since it is a non – terminating and non–recurring decimal).
(vi) \(\frac { \sqrt { 2 } }{ 2 } =\frac { \sqrt { 2 } }{ \sqrt { 2 } \times \sqrt { 2 } } =\frac { 1 }{ \sqrt { 2 } } \) is an irrational number ( since 2 is not a perfect square number).
3.

n(A - B) = 32 + x, n(B A) = 5x
n(A \(\cap\) B) = x
From the Venn diagram:
Given n(A) = n(B)
32 + x + x = x + 5x
32 + 2x = 6x
32 = 6x - 2x
32 = 4x
x = \({32\over 4}=8\)
The value of x = 8.
4.

Let T be the set of families buy Tamil news Papers
Let E be the set of families buy English news Papers
n(TUE) = 100
n(T) = 65 and n(E) = 55
Let "X" be the number families buy both newspapers.
By using venn-diagram
From the venn-diagrarn we get
65 - x + x + 55 - x = 100
120 - x = 100
120 -100 = x
20 = x
(i) Families buy both newspapers = 20
(ii) Families buy Tamil newspapers only = 65 - x
= 65 - 20
= 45
(iii) Families buy English newspapers only = 55 - x
= 55 - 20
= 35.
5.
| S.No | Polynomial | Based on number of terms | Based on their degree |
|---|---|---|---|
| 1 | \(\frac { { x }^{ 2 } }{ \sqrt { 2 } } +x+1\) | Trinomial | Quadratic Polynomial |
| 2 | \(\sqrt { 5 } { x }^{ 2 }-\frac { 6 }{ 5 } x\) | Binomial | Quadratic Polynomial |
| 3 | 1 | Monomial | Constant Polynomial |
| 4 | \({ m }^{ 4 }-\frac { 6 }{ 7 } { m }^{ 2 }-6m+2.7\) | Multinomial | Quadratic Polynomial |
| 5 | \(\frac { { t }^{ 3 } }{ \sqrt { 6 } } +\frac { { t }^{ 4 } }{ 4 } -t \) | Trinomial | Quadratic Polynomial |
6.
\(1\over 13\) = 0.07692307 .........
= \(0.\overline{076923}\)

Length of the period of decimal is 6.
7.
Length of the rectangle = 3x + 2 units
Breadth of the rectangle = 3x - 2 units
Area of the rectangle = (3x + 2 ) (3x - 2)
= 9x2 - 6x + 6x - 4
= 9x2- 4
When x = 20
Area of the rectangle = 9(20)2 - 4
= 9(400) - 4
= 3600 - 4 = 3596 sq.units.
8.
ABCD is a parallelogram AP and BP are bisectors of consecutive angles ∠A and ∠B.
Since the consecutive angles of a parallelogram are supplementary
∠A + ∠B = 1800
\(\frac{1}{2}\angle{A} +\frac{1}{2}\angle{B}=\frac{180^{0}}{2}\)
⇒ ∠PAB + ∠PBA = 90O
In ΔAPB,
∠PAB + ∠APB + ∠PBA = 180O (angle sum property of triangle)
∠APB = 180O – [∠PAB + ∠PBA]
= 180O – 90O = 90O
Hence Proved.
9.
\({6\over 7}=0.\overline {857142}\)
\({12\over 13}=0.\overline{923076}\)

The two irrational numbers are 0.866142 ...and 0.903076.......
10.
Here A = (7, 10), B = (-2, 5), C = (3,-4)
\(AB=\sqrt { \left( { x }_{ 2 }-{ x }_{ 1 } \right) ^{ 2 }+\left( y_{ 2 }-y_{ 1 } \right) ^{ 2 } } \)
\(=\sqrt { \left( -2-7 \right) ^{ 2 }+\left( 5-10 \right) ^{ 2 } } \)
\(=\sqrt { \left( -9 \right) ^{ 2 }+\left( -5 \right) ^{ 2 } } \)
\(=\sqrt { \left( 81+25 \right) } \)
\(=\sqrt { 106 } \)
\(A{ B }^{ 2 }=106\)............1
\(BC=\sqrt { \left( { x }_{ 2 }-{ x }_{ 1 } \right) ^{ 2 }+\left( y_{ 2 }-y_{ 1 } \right) ^{ 2 } } \)
\(=\sqrt { \left( 3-\left( -2 \right) \right) ^{ 2 }+\left( -4-5 \right) ^{ 2 } } \)
\(=\sqrt { \left( 5 \right) ^{ 2 }+\left( -9 \right) ^{ 2 } } \)
\(=\sqrt { \left( 81+25 \right) } \)
\(=\sqrt { 106 } \)
\({ BC }^{ 2 }=106\)...............2
\(AC=\sqrt { \left( { x }_{ 2 }-{ x }_{ 1 } \right) ^{ 2 }+\left( y_{ 2 }-y_{ 1 } \right) ^{ 2 } } \)
\(=\sqrt { \left( 3-7 \right) ^{ 2 }+\left( -4-10 \right) ^{ 2 } } \)
\(=\sqrt { \left( -4 \right) ^{ 2 }+\left( -14 \right) ^{ 2 } } \)
\(=\sqrt { \left( 16+196 \right) } \)
\(=\sqrt { 212 } \)
\({ AC }^{ 2 }=212\)..........3
From (1), (2) & (3) we get
AB2+BC2 = 106 +106 = 212 = AC2
AB2 + BC2 = AC2
ΔABC is a right angled triangle, right angled at B.
9th Standard Syllabus & Materials
9th Standard
TN 9th Tamil உள்ளத்தின் சீர் - திருக்குறள் Important Questions And Answers Study Material - QB365 Set A
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Tamilnadu Stateboard 9th Standard Subjects
Tamilnadu Stateboard Standards