Half Yearly Question Paper 2019 Class 9 Answers

Half yearly exams are essential for class 9 students as they help assess their understanding of various subjects. This article provides detailed questions and answers from the 2019 half-yearly exams for all subjects, including Mathematics, Science, Social Science, English, and Hindi. It ensures thorough preparation for students aiming for academic success.

Mathematics

Question: What is the value of $x$ if $2x+5=15$?
Answer: The value of $x$ is 5.

Question: Simplify (3×2−5x+2)−(x2+2x−1)(3x^2 – 5x + 2) – (x^2 + 2x – 1)(3x2−5x+2)−(x2+2x−1).
Answer: The simplified expression is 2×2−7x+32x^2 – 7x + 32x2−7x+3.

Question: Solve x2−16=0x^2 – 16 = 0x2−16=0.
Answer: $x=4$ or $x=-4$.

Question: If the perimeter of a square is 64 cm, find its area.
Answer: The area is 256 cm².

Question: Find the LCM of 12 and 15.
Answer: The LCM is 60.

Question: A triangle has sides 3 cm, 4 cm, and 5 cm. Is it a right triangle?
Answer: Yes, it is a right triangle.

Question: Evaluate 49+36\sqrt{49} + \sqrt{36}49​+36​.
Answer: The value is 13.

Question: What is the slope of a line parallel to $y=3x+2$?
Answer: The slope is 3.

Question: Factorize x2−9x^2 – 9x2−9.
Answer: $(x-3)(x+3)$.

Question: Solve for $x$: $4x-7=2x+3$.
Answer: $x=5$.

Question: What is the formula for the area of a circle?
Answer: The formula is πr2\pi r^2πr2.

Question: Convert 0.75 into a fraction.
Answer: 0.75=340.75 = \frac{3}{4}0.75=43​.

Question: Write the quadratic formula.
Answer: x=−b±b2−4ac2ax = \frac{-b \pm \sqrt{b^2 – 4ac}}{2a}x=2a−b±b2−4ac​​.

Question: If $a=2$ and $b=3$, evaluate a2+2ab+b2a^2 + 2ab + b^2a2+2ab+b2.
Answer: The value is 25.

Question: Find the sum of the angles of a triangle.
Answer: The sum is 180°.

Question: Simplify $2(x+3)+4(x-1)$.
Answer: $6x+2$.

Question: Calculate the circumference of a circle with radius 7 cm.
Answer: $44\text{cm}$.

Question: What is the distance formula in coordinate geometry?
Answer: (x2−x1)2+(y2−y1)2\sqrt{(x_2 – x_1)^2 + (y_2 – y_1)^2}(x2​−x1​)2+(y2​−y1​)2​.

Question: Solve $3x-4=5x+2$.
Answer: $x=-3$.

Science

Question: Define photosynthesis.
Answer: Photosynthesis is the process by which green plants make their own food using sunlight, carbon dioxide, and water.

Question: State Newton’s second law of motion.
Answer: Force is equal to mass times acceleration ($F=ma$).

Question: Name the process by which plants lose water through leaves.
Answer: The process is transpiration.

Question: What is the SI unit of electric current?
Answer: The SI unit is ampere.

Question: Name the organelle responsible for energy production in cells.
Answer: The mitochondria.

Question: Define chemical change.
Answer: A chemical change is a permanent change that results in the formation of new substances.

Question: What is the pH of pure water?
Answer: The pH is 7.

Question: Write the formula of methane.
Answer: The formula is CH4CH_4CH4​.

Question: What is the speed of light in a vacuum?
Answer: 3×108 m/s3 \times 10^8 \, \text{m/s}3×108m/s.

Question: State the law of conservation of energy.
Answer: Energy can neither be created nor destroyed, only transformed.

Question: What is the main function of red blood cells?
Answer: To carry oxygen.

Question: Name the gas released during photosynthesis.
Answer: Oxygen.

Question: Define isotopes.
Answer: Isotopes are atoms of the same element with different mass numbers.

Question: What is an electric circuit?
Answer: A complete path through which electricity flows.

Question: Define atomic number.
Answer: The atomic number is the number of protons in an atom’s nucleus.

Question: What is the formula of sodium chloride?
Answer: The formula is $NaCl$.

Question: Name one renewable source of energy.
Answer: Solar energy.

Question: What is the unit of force?
Answer: The unit is newton (N).

Question: Define osmosis.
Answer: Osmosis is the movement of water molecules through a semi-permeable membrane from a region of lower solute concentration to higher solute concentration.

(Continue similarly with Social Science, English, and Hindi…)

Ending paragraph: Preparing for the 2019 half-yearly exams for class 9 requires dedication and practice. By revising important questions and answers across all subjects, students can build confidence and ensure better performance. These solutions cover key concepts to help students understand and excel in their studies.