Class 10 Maths - Chapter 7: Coordinate Geometry
Notes
1. Introduction
Coordinate geometry helps us study geometry using algebra. Points are represented on a
coordinate plane using (x, y).
2. Distance Formula
Distance between two points A(x1, y1) and B(x2, y2):
d = โ[(x2 - x1)ยฒ + (y2 - y1)ยฒ]
3. Section Formula
To find a point dividing a line segment in ratio m:n:
P(x, y) = [(mx2 + nx1)/(m+n), (my2 + ny1)/(m+n)]
4. Midpoint Formula
Midpoint of line joining A(x1, y1) and B(x2, y2):
M = [(x1 + x2)/2, (y1 + y2)/2]
5. Area of Triangle
If three points A(x1,y1), B(x2,y2), C(x3,y3) are given:
Area = 1/2 |x1(y2 - y3) + x2(y3 - y1) + x3(y1 - y2)|
6. Collinearity Condition
If area of triangle formed by three points is zero, then points are collinear.
7. Important Tips
โข Always write coordinates correctly.
โข Be careful with signs.
โข Practice numerical problems.
