9th Linear Equation in two Variable [Guess paper] 2013

9th Linear Equation in two Variable [Sample Guess paper] 2013

[1 Mark Questions]

1. Which of the following is not a linear equation?

(a) ax + by + c = 0                 (b) 0x + 0y + c = 0              

(c) 0x + by + c = 0                 (d) ax + 0y + c = 0

2. Age of ‘x’ exceeds age of ‘y’ by 7 yrs. This statement can be expressed as linear equation as  

(a) x + y + 7 = 0                  (b) x – y + 7 = 0      

(c) x – y – 7 = 0                  (d) x + y – 7 = 0

3. Linear equation in one variable is :

(a) 2x = y      (b) y2 = 3y + 5   (c) 4x – y = 5   (d) 3t + 5 = 9t – 7

4. The condition that the equation ax + by + c = 0 represent a linear equation in two variables is

(a) a ≠ 0, b = 0              (b) b ≠ 0, a = 0               

c) a = 0, b = 0               (d) a ≠ 0, b ≠ 0             

5. How many linear equations in x and y can be satisfied by x = 1 and y = 2?

(a) only one   (b) two  (c) infinitely many (d) three

6. The general form of a linear equation in two variables is :

(a) ax + by + c = 0, where a, b, c are real  umbers and a, b ≠ 0  

(b) ax + b = 0, where a, b are real numbers and a ≠0

(c) ax² + bx + c = 0, where a, b, c are real numbers and a, b ≠ 0    

(d) none of these

7. The equation of the line whose graph passes through the origin, is :  

8th Polygons Solved Questions Paper[CBSE Maths]

1.Q. Find the number of diagonals in an octagon?

Ans: Number Of Diagonals Of Polygon = n(n-3) / 2     

Where n is Number Of Sides

Here n = 8

Diagonals= [8(8-3)5]/2 = 20

2.Q. Find the number of sides of a polygon whose each exterior angle is 45⁰ .

Ans: Measure of Each Exterior Angle of a Polygon = 360/n

Each Exterior Angle = 45

45 = 360/n

Number of Sides = 360/45 =8

So Number of Sides = 8

3. Q. The sum of the interior angles of a regular polygon is 3 times the sum of its exterior angles. Determine the number of sides of the polygon.

Ans: sum of the interior angles of a regular polygon is 3 times the sum of its exterior angles.

We know that in a regular polygon sum of all the exterior angles = 360°

Therefore, sum of interior angles = 3 × 360° = 1080°

Again, we have sum of interior angles, S = (n - 2)180°, where n is the number of sides of the polygon

⇒ (n - 2)180° = 1080°
⇒ n - 2 = 6
⇒ n = 8
4. Q.  (a) What is the minimum interior angle possible for a regular polygon? Why?

 (b) What is the maximum exterior angle possible for a regular polygon?

Answer: The polygon with minimum number of sides is a triangle, and each angle of an equilateral triangle measures 60°, so 60° is the minimum value of the possible interior angle for a regular polygon. For an equilateral triangle the exterior angle is 180°-60°=120° and this is the maximum possible value of an exterior angle for a regular polygon.
The sum of the exterior angles of any polygon= 360⁰
Hence, the polygon of 8 sides is octagon.

5. Q. Find the measure of each exterior angle of a regular polygon of 9 sides.

Ans: Total measure of all exterior angles = 360

No. of sides = 9

Measure of each exterior angle = 360/9 = 40

6.Q. If the sum of the measures of the interior angles of a polygon equals the sum of the measures of the exterior angles, how many sides does the polygon have?

8th Maths Practice Paper-1

1. An altitude of a triangle is 5/3 of its corresponding base. If the altitude were increased by 4 cm and the base decreased by 2 cm, the area of the triangle would remain the same.Find the base and altitude of the triangle.

2. Some toffees are bought at the rate of 11 for Rs. 10 and same numbers are bought at the rate of 9 for Rs 10. If the whole lot is sold at one rupee per toffee, find the gain or loss percent.

3. Chandu purchased a watch at 20% discount on its marked price but sold it at marked price. Find the gain percent of Chandu on this transaction.

4. A motorboat covers a certain distance downstream in a river in five hours. It covers the same distance upstream in five hours and half. The speed of water is 1.5 km/hr. Find the speed of the boat in still water.

5. Factorize: x6 – 3x4y2 +3x2y4 –y6

6. Evaluate: (367/2 –369/2)/ 365/2

7. Divide 34x-22x3-12x4-10x2-75 by (3x+7) and check your answer.

8. The digit in the tens place of a number is three times that in the ones place. If the digits  are reversed, the new number will be 36 less than the original number. Find the number.

9. A well is dug 20m deep and it has a diameter 7m. The earth, which is so dug out, is spread out on a rectangular plot 22m long and 14m broad. What is the height of the platform so formed?

10. The total surface area of a hollow cylinder open at both ends is 4620 sqcm, area of the base ring is 115.5sqcm and height 7cm. find the thickness of the cylinder.

11. A hemispherical bowl is made of steel 0.5cm thick. The inside radius of the bowl is 4cm. Find the volume of steel used in making the bowl.

12. A circus tent is cylindrical up to a height of 3m and conical above it .If the radius of the base is 49m and the slant height of the conical part is 53m, find the total canvas required to make the tent.

13. A storage tank consists of a circular cylinder with hemispherical ends on both the sides. If  the external diameter of the cylinder be 1.4m and length be 5m. What will be the cost of painting it on the outside at the rate of Rs10 per sq. cm?

14. The difference between the compound interest and simple interest on a certain sum of money for two years at 7.5% per annum is Rs 360. Find the sum.

15. At what rate % per annum will a sum of Rs 4000 yield compound interest of Rs 410 in two years?

16. Diagonal of a parallelogram bisect at the point O . XY is a line segment passing through O such that X lies on AD and Y lies on BC. Give reasons for each of the following
(i) OB=OD ((ii)DBOYcongruent DDOX.

8th Maths Practice Paper-1 Download  full Question paper pdf

8th Direct and Inverse Variation and Profit, Loss ... - cbse math study

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These were sold at 8%gain and 4% loss respectively. Find his gain orloss percent in the whole transaction. Q-11. Some toffees are bought at the rate of11 per Rs.10 and sold at the rate of 9 per Rs.10. If the whole lot is sold at one rupee per toffee, find his gain or loss percent on the whole transaction.