Question

Q.3) Fill in the blanks:
(1 markt
(1) ABC is an equilateral triangle of side a. Its area will be
(ii) The distance of the point (a, b) from the origin is​

Answer 1

Answer 1. √3/2 * (a^2) sq. units

ii. √a^2 + b^2 units

Step-by-step explanation:

1. All the sides are equal. so by Herons formula

S = (a + a + a )/2 = 3a/2

area = √s(s-a)(s-b)(s-c) sq. units

here √3a/2(3a/2-a)(3a/2-a)(3a/2- a)

=√(3a/2)(a/2)(a/2)(a/2)

=√3a⁴/16

= √3/2 * (a²) sq. units

2. Formula to find distance between two points is √(X2 - X1)²+ (y2 -y1)²

origin (0,0) and (a,b)

here X1 =0 y1 = 0

X2 =a y2 = b

then we have √(a - 0)² +(b - 0)²

√a² + b² units.