Prev Question 5 Coordinated Geometry - Exercise 7.3 Next
Answer:
Let the ratio in which x-axis divides the line segment joining (–4, –6) and (–1, 7) = 1: k. Then, x-coordinate becomes, \frac{\left(-1-4k\right)}{(k+1)} y-coordinate becomes, \frac{\left(7-6k\right)}{(k+1)} Since P lies on x-axis, y coordinate = 0 \frac{\left(7-6k\right)}{(k+1)}=0\\ 7-6k=0\\ k=\frac{7}{6} Therefore, the point of division divides the line segment in the ratio 6 : 7. Now, m1 = 6 and m2 = 7 By using the section formula, x=\frac{\left(m_1x_2+m_2x_2\right)}{(m_1+m_2)}=\frac{\left[6(-1)+7(-4)\right]}{(6+7)}=\frac{\left(-6-28\right)}{13}=-\frac{34}{13}\\ So,\ now\\ y=\frac{\left[6(7)+7(-6)\right]}{(6+7)}=\frac{\left(42-42\right)}{13}=0 Hence, the coordinates of P are (-34/13, 0)
Was This helpful? Application deadline for HTET 2022 extended. The candidates can now apply online till 30th September 2022. The exam is conducted by the Board of School Education, Haryana to shortlist eligible candidates for PGT and TGT posts in Government schools across Haryana. The exam is conducted for 150 marks. The HTET Exam Pattern for Level I, Level II, and Level III exams is different. There will be no negative marking in the exam. In what ratio is the line joining (2, -4) and (-3, 6) divided by the y – axis. Let the line joining points A (2, -4) and B (-3, 6) be divided by point P (0, y) in the ratio k : 1. `x=(kx_2+x_1)/(k+1)` `0=(kxx(-3)+1xx2)/(k+1)` `0=-3k+2` `k=2/3` Thus, the required ratio is 2: 3. Concept: Co-ordinates Expressed as (x,y) Is there an error in this question or solution? Page 2In what ratio does the point (1, a) divide the join of (-1, 4) and (4,-1)? Also, find the value of a. Let the point P (1, a) divides the line segment AB in the ratio k: 1. `1=(4k-1)/(k+1)` `=>k+1=4k-1` `=>2=3k` `=>k=2/3` ............(1) `=>a=(-k+4)/(k+1)` `=> a = (-2/3 + 4)/(2/3 + 1)` (from 1) `=> a = 10/5 = 2` Hence, the required is 2 : 3 and the value of a is 2. Concept: Co-ordinates Expressed as (x,y) Is there an error in this question or solution? Page 3In what ratio does the point (a, 6) divide the join of (-4, 3) and (2, 8)? Also, find the value of a. Let the point P (a, 6) divides the line segment joining A (-4, 3) and B (2, 8) in the ratio k: 1. `6=(8k+3)/(k+1)` `=> 6k+6=8k+3` `=>3=2k` `=>k=3/2` .................(1) `=>a=(2k-4)/(k+1)` `=>a=(2xx3/2-4)/(3/2+1)` (from equation 1) `=>a=-2/5` Hence, the required ratio is 3:2 and the value of a is `-2/5` Is there an error in this question or solution? |