Use graph paper for this question. Take 2 cm = 1 unit on both axes.
(i) Draw the graphs of x + y + 3 = 0 and 3x - 2y + 4 = 0. Plot three points per line.
(ii) Write down the coordinates of the point of intersection of the lines.
(iii) Measure and record the distance of the point of intersection of the lines from the origin in cm.

Question

Use graph paper for this question. Take 2 cm = 1 unit on both axes.
(i) Draw the graphs of x + y + 3 = 0 and 3x - 2y + 4 = 0. Plot three points per line.
(ii) Write down the coordinates of the point of intersection of the lines.
(iii) Measure and record the distance of the point of intersection of the lines from the origin in cm.

KnowledgeBoat · Accepted Answer

(i) Given, ⇒ x + y + 3 = 0 ⇒ y = -(3 + x) .........(1) When x = -1, y = -[3 + (-1)] = -(3 - 1) = -2, x = 0, y = -(3 + 0) = -3, x = 1, y = -(3 + 1) = -4. Table of values for equation (1) x | -1 | 0 | 1 ---- | ---- | ---- | ---- y | -2 | -3 | -4 Steps of construction : 1. Plot the points (-1, -2), (0, -3) and (1, -4) on graph paper. 2. Connect points by straight line. Given, ⇒ 3x - 2y + 4 = 0 ⇒ 2y = 3x + 4 ⇒ y = When x = -2, y = = -1, x = 0, y = = 2, x = 2, y = = 5. Table of values for equation (2) x | -2 | 0 | 2 ---- | ---- | ---- | ---- y | -1 | 2 | 5 Steps of construction : 1. Plot the points (-2, -1), (0, 2) and (2, 5) on graph paper. 2. Connect points by straight line. (ii) From graph, P(-2, -1) is the intersection of lines. Hence, coordinates of point of intersection = (-2, -1). (iii) From P, draw a perpendicular to y-axis. As, 1 unit = 2 cm. So, PQ = 2 unit = 4 cm, OQ = 1 unit = 2 cm. In right angle triangle, By pythagoras theorem, ⇒ OP² = PQ² + OQ² ⇒ OP² = 4² + 2² ⇒ OP² = 16 + 4 ⇒ OP² = 20 ⇒ OP = = 4.5 cm Hence, distance of the point of intersection of the lines from the origin = 4.5 cm.

Mathematics

Coordinate Geometry

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Use graph paper for this question :
(i) Draw the graphs of 3x - y - 2 = 0 and 2x + y - 8 = 0. Take 1 cm = 1 unit on both axes and plot three points per line.
(ii) Write down the coordinates of the point of intersection and the area of the triangle formed by the lines and the x-axis.