Coordinate Geometry

ABCD is a rectangle formed by the points A (-1, – 1), B (-1, 4), C (5, 4) and D (5, -1). P, Q, R and S are the midpoints of AB, BC, CD and DA respectively. Is the quadrilateral PQRS a square? a rectangle? or a rhombus? Justify your answer.

Solution: The side AB has P as a mid-point, Coordinate of P = ( (-1 – 1)/2, (-1 + 4)/2 ) = (-1, 3/2) In the same way, Q, R, and S are (As Q is mid-point of BC, R is midpoint of CD and S is...

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The vertices of a βˆ† ABC are A (4, 6), B (1, 5) and C (7, 2). A line is drawn to intersect sides AB and AC at D and E respectively, such that AD/AB = AE/AC = 1/4. Calculate the area of the βˆ† ADE and compare it with area of βˆ† ABC. (Recall Theorem 6.2 and Theorem 6.6)

Given that: A (4, 6), B (1, 5) and C (7, 2) are the vertices of a βˆ†ABC. AD/AB = AE/AC = 1/4 AD/(AD + BD) = AE/(AE + EC) = 1/4 Points D and E divide AB and AC in a 1:3 ratio, respectively. D's...

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The class X students of a secondary school in Krishinagar have been allotted a rectangular plot of land for their gardening activity. Saplings of Gulmohar are planted on the boundary at a distance of 1 m from each other. There is a triangular lawn in the plot as shown in the fig. 7.14. The students are to sow the seeds of flowering plants on the remaining area of the plot.

(i) Taking A as origin, find the coordinates of the vertices of the triangle. (ii) What will be the coordinates of the vertices of triangle PQR if C is the origin?Also calculate the areas of the...

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To conduct Sports Day activities, in your rectangular shaped school ground ABCD, lines have been drawn with chalk powder at a distance of 1 m each. 100 flower pots have been placed at a distance of 1 m from each other along AD, as shown in the following figure. Niharika runs 1/4 th the distance AD on the 2nd line and posts a green flag. Preet runs 1/5th the distance AD on the eighth line and posts a red flag. What is the distance between both the flags? If Rashmi has to post a blue flag exactly halfway between the line segment joining the two flags, where should she post her flag?

We concluded from the given instructions that Niharika placed the green flag at 1/4th of the distance AD, or (1/4 Γ—100) m = 25 metres from the 2nd line's starting point. As a result, this...

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In a classroom, 4 friends are seated at the points A, B, C and D as shown in Fig. 7.8. Champa and Chameli walk into the class and after observing for a few minutes Champa asks Chameli, β€œDon’t you think ABCD is a square?” Chameli disagrees. Using distance formula, find which of them is correct.

Solution: The coordinates of points A, B, C, and D are (3, 4), (6, 7), (9, 4) and (6, 1), respectively, as shown in the figure. Using the distance formula, we can calculate the distance between two...

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 Find the distance between the following pairs of points:

(i) (2, 3), (4, 1) (ii) (-5, 7), (-1, 3) Solutions: The distance formula, say d, is used to calculate the distance between two points (x1, y1) and (x2, y2), $d=\sqrt{{{\left( {{x}_{2}}-{{x}_{1}}...

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