Use app×
QUIZARD
QUIZARD
JEE MAIN 2026 Crash Course
NEET 2026 Crash Course
CLASS 12 FOUNDATION COURSE
CLASS 10 FOUNDATION COURSE
CLASS 9 FOUNDATION COURSE
CLASS 8 FOUNDATION COURSE
+1 vote
1.5k views
in Geometry by (115k points)
closed by
The foot of the perpendicular from (2, 3) upon the line 4x - 5y + 8 = 0 is
1. (0 ,0)
2. (1, 1)
3. \(\left( {\frac{{41}}{{78}},\frac{{128}}{{75}}} \right)\)
4. \(\left( {\frac{{78}}{{41}},\frac{{128}}{{41}}} \right)\)

1 Answer

0 votes
by (113k points)
selected by
 
Best answer
Correct Answer - Option 4 : \(\left( {\frac{{78}}{{41}},\frac{{128}}{{41}}} \right)\)

Calculation:

Let (h, k) be the coordinates of the foot of the perpendicular from the point (2, 3) on the line 4x - 5y + 8 = 0.

The slope of the perpendicular line will be \(\frac{k - 3}{h - 2}\)

The slope of the line 4x - 5y + 8 = 0

⇒ 4x - 5y + 8 = 0

⇒ -5y = -4x - 8

⇒ y = 4/5x + 8/5

On comparing the above equation with y = mx + c we get m = 4/5

∴ the slope of the line is 4/5

Using the condition of perpendicularity of lines,

\(\frac{k - 3}{h - 2} \times \frac{4}{5} = -1\)

4k - 12 = - 5h + 10

4k + 5h = 22       ----(i)

Since (h, k) lies on the given line 4x - 5y + 8 = 0,

⇒ 4h - 5k + 8 = 0

⇒ 4h - 5k = - 8       ----(ii)

on solving the equations (i) and (ii) using elimination method, we get h = 78/41 and k = 128/41

Therefore, \(\left( {\frac{{78}}{{41}},\frac{{128}}{{41}}} \right)\)are the coordinates of the foot of the perpendicular from the point (2, 3) on the line 4x - 5y +8 = 0.

Welcome to Sarthaks eConnect: A unique platform where students can interact with teachers/experts/students to get solutions to their queries. Students (upto class 10+2) preparing for All Government Exams, CBSE Board Exam, ICSE Board Exam, State Board Exam, JEE (Mains+Advance) and NEET can ask questions from any subject and get quick answers by subject teachers/ experts/mentors/students.

Categories

...