Everything you need to ace this chapter, in one place.
Notes · Mind Map · Quiz · Assertion-Reason · Case Studies · Question Bank · Past Papers
Q1. A student plots points A(3, 0), B(7, 0), C(7, 4), and D(3, 4) on a coordinate plane and claims they form a square. Which property must be verified to confirm this claim is incorrect?
Answer: D — These points form a rectangle (not a square) because while all angles are 90°, opposite sides are equal but adjacent sides are not equal (AB = 4, BC = 4 appears equal, but actually AB=4 and BC=4 make it a square only if verified carefully—the error is that the figure IS actually a square here, so the trap is students must recognize BOTH conditions are needed; the distractor A tests whether students think equal sides alone suffice).
Q2. Two points P(x₁, y₁) and Q(x₂, y₂) lie on a line parallel to the x-axis. Which statement correctly describes the distance between them using the distance formula?
Answer: A — The distance formula always applies; when y₁ = y₂, the formula correctly simplifies to |x₂ – x₁|, showing the formula's generality—option B is incomplete phrasing and D confuses 'parallel to x-axis' with vertical distance.
Q3. Assertion (A): If three points form a right triangle, then the sum of squares of two sides equals the square of the third side. Reason (R): The Pythagorean theorem states that in a right triangle, the square of the hypotenuse equals the sum of squares of the other two sides. Choose the correct option:
Answer: A — A correctly states the property in general form (which side is which depends on identifying the hypotenuse); R provides the exact theorem; R explains why A is true—the converse also holds, validating the statement.
Q4. A construction engineer claims: 'Any quadrilateral with all four sides equal is a square.' Which of the following best refutes this claim using properties from coordinate geometry?
Answer: A — A rhombus is a valid counterexample: all sides equal but diagonals unequal and angles not all 90°—option B is false (equal sides don't guarantee equal angles), C and D are false geometric claims.
Q5. Assertion (A): The distance of the point (5, –3) from the origin is √34. Reason (R): The distance of any point (x, y) from the origin O(0, 0) is given by OP = √(x² + y²). Choose the correct option:
Answer: A — R is the correct formula (derived from the distance formula with origin as reference); applying it: √(5² + (–3)²) = √(25 + 9) = √34, so A is true and R explains it.
Q6. A student uses the distance formula to find PQ where P(2, 3) and Q(2, 7). She calculates: PQ = √[(2–2)² + (7–3)²] = √[0 + 16] = 4. Which statement about her method is most accurate?
Answer: A — The distance formula is universally applicable; her calculation is correct—option C is true but doesn't make A wrong; option B and D are false misconceptions about formula restrictions.
Q7. Assertion (A): If points A, B, and C satisfy AB + BC = AC, then they are collinear (lie on the same line). Reason (R): The distance formula ensures that the sum of two sides of a triangle equals the third side only when the three vertices lie on a straight line. Choose the correct option:
Answer: A — Both A and R are true; R correctly explains A by invoking the triangle inequality—equality holds only in the degenerate case of collinearity.
Q8. Two points P and Q are at distances d₁ and d₂ from the origin respectively. A student claims: 'The distance PQ is always equal to |d₁ – d₂|.' Is this claim valid?
Answer: C — The relationship PQ = |d₁ – d₂| holds only when O, P, Q are collinear and P, Q are on the same side of O (or opposite sides in specific arrangements); in general, PQ depends on the angle between OP and OQ, not just the distances—option C is the correct conditional statement.
Q9. Assertion (A): The points (0, 0), (1, 1), and (2, 2) do not form a triangle. Reason (R): The sum of two sides of a degenerate triangle equals the third side, which occurs when the distance formula gives a zero sum for the triangle inequality. Choose the correct option:
Answer: C — A is true (the three points are collinear); R's phrasing is convoluted and imprecise—the correct reason is that collinear points fail the strict triangle inequality, not because of a 'zero sum' in the distance formula itself.
Q10. A surveyor measures the coordinates of three landmarks: A(0, 0), B(3, 4), and C(6, 8). She wants to verify if they are collinear using coordinate geometry. Which approach is most reliable?
Answer: A — Option A directly applies the collinearity condition (equality in triangle inequality)—options B is imprecise; C requires computing slope (not introduced in this chapter); D is valid but depends on the area formula (not covered here).
What is the distance formula for two points P(x₁, y₁) and Q(x₂, y₂)?
PQ = √[(x₂−x₁)² + (y₂−y₁)²], which uses Pythagoras theorem applied to coordinate differences.
What is the distance of point P(x, y) from the origin O(0, 0)?
OP = √(x² + y²), which is the distance formula with the origin as reference point.
How do you prove three points are collinear using distances?
Calculate distances AB, BC, and AC; if AB + BC = AC, then points lie on the same line.
What condition must be satisfied for a point P(x, y) to be equidistant from A(x₁, y₁) and B(x₂, y₂)?
AP² = BP², which when expanded and simplified gives a linear equation in x and y.
How do you verify that four points form a square using distance formula?
Check that all four sides are equal AND both diagonals are equal, or check sides equal and one angle is 90°.
What is the relationship between distances in a right triangle verified by distance formula?
If AB² + BC² = AC², then by Pythagoras converse, angle B is 90°, confirming a right angle.
If points A(4, 0) and B(6, 0) lie on the x-axis, what is AB?
AB = |6 − 4| = 2 units, since points on the same axis only have coordinate differences in that direction.
What are the coordinates of a point on the x-axis and on the y-axis?
Points on x-axis have form (x, 0) and points on y-axis have form (0, y).
Why can distance never be negative even if (x₂−x₁) or (y₂−y₁) is negative?
Because we square the differences (negative squared becomes positive) and take only the positive square root.
How does the distance formula help in classifying quadrilaterals?
By computing all side lengths and diagonals, we identify if sides are equal, perpendicular angles exist, and determine if shape is square, rectangle, or rhombus.
Define abscissa and ordinate of a point. Write the coordinates of a point lying on the x-axis and a point lying on the y-axis. [2 marks]
Abscissa is distance from y-axis (x-coordinate); ordinate is distance from x-axis (y-coordinate). Points on x-axis have y = 0; points on y-axis have x = 0.
Show that the points A(1, 1), B(5, 5), and C(9, 9) are collinear. Use the distance formula to justify your answer. [3 marks]
Calculate AB, BC, and AC using distance formula; verify if AB + BC = AC to prove collinearity. AB = 4√2, BC = 4√2, AC = 8√2.
Prove that the points A(0, 0), B(3, 4), C(3, 8), and D(0, 4) form a rectangle. Verify that the diagonals are equal and find the area of the rectangle. [5 marks]
Calculate all four sides (AB = 5, BC = 4, CD = 5, DA = 4) showing opposite sides equal; calculate both diagonals AC = BD = 5 using distance formula proving diagonals are equal; area = length × width using side lengths and perpendicularity verified through distance relationships.
Q1. Assertion (A):
The distance of a point P(x, y) from the origin O(0, 0) is given by OP = √(x² + y²).
Reason (R):
This formula is derived by applying Pythagoras theorem to the right triangle formed by the origin, the point, and its projection on the x-axis.
Answer: A — Both A and R are true, and R is the correct explanation of A — Both the assertion and reason are true, and the reason correctly explains why the formula for distance from origin takes this specific form. The Pythagoras theorem is indeed the foundation for deriving this distance formula.
Q2. Assertion (A):
If three points A, B, C satisfy AB + BC = AC, then they are collinear with B between A and C.
Reason (R):
The distance formula proves that when distances satisfy this property, all three points must lie on the same straight line.
Answer: B — Both A and R are true, but R is NOT the correct explanation of A — The assertion is true - three points are collinear when the sum of two distances equals the third. However, the reason is not the correct explanation because the distance formula itself doesn't 'prove' collinearity; rather, the property AB + BC = AC is the definition/criterion for collinearity in coordinate geometry.
Q3. Assertion (A):
A quadrilateral with all four sides equal must be a square.
Reason (R):
A square is a quadrilateral with all sides equal and all angles equal to 90 degrees.
Answer: D — A is false but R is true — The assertion is false because a quadrilateral with all four sides equal is a rhombus, not necessarily a square. A square requires additional conditions like equal angles or equal diagonals. The reason is true, but since the assertion is false, the answer is D.
Unlock more Assertion-Reason questions in Premium — unlock →
Case Study:
A city planner is designing a park with three entry gates located at coordinates A(2, 3), B(8, 6), and C(5, 9). The planner wants to determine if these gates form a right-angled triangle for better traffic management. Using the distance formula, she needs to calculate the distances between each pair of gates and check if they satisfy the Pythagoras theorem condition.
Q1. What is the distance between gate A(2, 3) and gate B(8, 6)?
Answer: A
Q2. What is the distance between gate B(8, 6) and gate C(5, 9)?
Answer: A
Q3. What is the distance between gate A(2, 3) and gate C(5, 9)?
Answer: C
Q4. Do the three gates form a right-angled triangle?
Answer: D
Unlock more case studies in Premium — unlock →
Real CBSE board exam questions from past papers — free to attempt.
CBSE 2026 · Set 31/4/1 · 1 mark
The distance between the points (– 4, 2) and (1, 0) is:
CBSE 2026 · Set 31/4/1 · 2 marks
A (– 2, 3) and B (4, 1) are end points of the diameter of a semi-circle. The semi-circle intersects y-axis at point P. Find the co-ordinates of the point P.
CBSE 2026 · Set 31/4/1 · 3 marks
The vertices of a rhombus ABCD are A(– 3, – 4), B(5, – 3), C(1, 4) and D(– 7, 3). Find the length of both the diagonals. Hence, find area of the rhombus ABCD.
CBSE 2026 · Set 31/4/2 · 1 mark
The distance between the points (– 5, 1) and (2, 2) is:
CBSE 2026 · Set 31/4/3 · 1 mark
The distance between the points (–1, 22) and (2, 2) is:
CBSE 2026 · Set 31/4/3 · 2 marks
The vertices of a ABC are A(–1, 3), B(2, –3) and C(4, 5). Find the coordinates of a point P on median AD such that AP : PD = 2 : 3.
CBSE 2026 · Set 31/4/3 · 3 marks
The vertices of a rhombus ABCD are A(–3, –4), B(5, –3), C(1, 4) and D(–7, 3). Find the length of both the diagonals. Hence, find area of the rhombus ABCD.
CBSE 2026 · Set 31/5/1 · 1 mark
The distance between the points (–2, 5) and (5, –2) is
CBSE 2026 · Set 31/5/1 · 2 marks
If A(a, 0), B(1, 1) and C(0, b) form a triangle, right angled at B when joined, then establish a relation between a and b.
CBSE 2026 · Set 31/5/1 · 3 marks
Points P(6, 0), Q(2, 8) and R(–2, 4) are vertices of △PQR. It is given that MN || QR such that PM/MQ = 1/3. Using distance formula and ratio formula, show that MN/QR = 1/4.
CBSE 2026 · Set 31/5/2 · 1 mark
The distance between the points (–4, 5) and (–1, 2) is
CBSE 2026 · Set 31/5/3 · 3 marks
Determine the ratio in which the line 2x + y = 6 divides the line segment joining the points (1, 3) and (2, 5).
See all 117 board PYQs for this chapter — open PYQ tab →
Every formula from all 14 chapters on one page, checked against the NCERT textbook and the CBSE 2026-27 syllabus. Free PDF download.
All 1107 CBSE board questions from 2022–2026, sorted by chapter and question type. Free PDF download.
You've seen the free preview. Open the full interactive study kit — mind map, instant-graded quiz, progress tracking — free, no sign-in required.
Open Full Study Kit — Free →Premium unlocks the full Question Bank, Daily Practice Papers, Chapter Quiz and Full Mock Papers for every chapter.