10th Maths 7.3
NCERT Class 10th solution of Exercise 7.1 NCERT Class 10th solution of Exercise 7.2 NCERT Class 10th solution of Exercise 8.1 NCERT Class 10th Maths Projects Exercise 7.3 Q1. Find the area of the triangle whose vertices are: i) `(2, 3), (-1, 0), (2, -4)` ii) `(-5, -1), (3, -5), (5, 2)` Sol. : i) Given: Let `A(2, 3), B(-1, 0),` and `C(2, -4)` Solve: Area of `triangle=1/2[x_1(y_2-y_3)+x_2(y_3-y_1)+x_3(y_1-y_2)]` `ar(ABC)=1/2[2(0+4)+(-1)(-4-3)+2(3-0)]` `ar(ABC)=1/2[2(4)+(-1)(-7)+2(3)]` `ar(ABC)=1/2[8+7+6]` `ar(ABC)=21/2` square units Answer: The area of `triangleABC` is `21/2` square units. ii) Given: Let `A(-5, -1), B(3, -5),` and `C(5, 2)` Solve: Area of `triangle=1/2[x_1(y_2-y_3)+x_2(y_3-y_1)+x_3(y_1-y_2)]` `ar(ABC)=1/2[-5(-5-2)+3(2+1)+5(-1+5)]` `ar(ABC)=1/2[-5(-7)+3(3)+5(4)]` `ar(ABC)=1/2[35+9+20]` `ar(ABC)=1/2[64]` `ar(ABC)=32` square units Answer: The area of `triangleABC` is `32` square units. Q2. In each of the following find the value of `k`, for which the points are collinear. i...