DP HCM09 Jan 2026Shift 3Coordinate Geometry

Find the equation of the line that passes through the point (2.25, 3.5) and is perpendicular to the line that passes through the points (1.25, 2.5) and (3.25, 4.5).

उस रेखा (Line) का समीकरण (Equation) ज्ञात कीजिए जो बिंदु (2.25, 3.5) से होकर गुजरती है तथा उस रेखा पर लंबवत है जो बिंदुओं (1.25, 2.5) तथा (3.25, 4.5) से होकर गुजरती है।

Answer और ExplanationAnswer and explanation

Answer: (B) 4x + 4y = 23

दी गई रेखा (Line) का ढाल (Slope) = 4.5 − 2.53.25 − 1.25 = 22 = 1
लंब (Perpendicular) ढाल = −1
(2.25, 3.5) से: y − 3.5 = −(x − 2.25) ⇒ x + y = 5.75
4 से गुणा करें: 4x + 4y = 23
✓
समीकरण (Equation) 4x + 4y = 23 है।
Slope of the given line = 4.5 − 2.53.25 − 1.25 = 22 = 1
Perpendicular slope = −1
Through (2.25, 3.5): y − 3.5 = −(x − 2.25) ⇒ x + y = 5.75
Multiply by 4: 4x + 4y = 23
✓
The equation is 4x + 4y = 23.
SMART APPROACH

ढाल (Slope) −1 का अर्थ है रूप x + y = k (यानी 4x + 4y = 4k)। बिंदु (Point) रखें: 4(2.25) + 4(3.5) = 9 + 14 = 23।

Slope −1 means the form x + y = k (4x + 4y = 4k). Put the point: 4(2.25) + 4(3.5) = 9 + 14 = 23.

Source: DP HCM · 09 Jan 2026 · Shift 3। Solution: Prashant Sir, Vijayastra।Source: DP HCM · 09 Jan 2026 · Shift 3. Solution by Prashant Sir, from Vijayastra.