Question

(1)  The area of a triangle whose vertices are (1, -1), (-4, 6) & (-3, -5) is ____________. (a) 24 square unit (b) -24 square unit (c) 20 square unit ( d) -20 square unit |///////say ans in a b C or d​

Answer 1

Answer:

Given that, the coordinates of the vertices of a triangle are (1,−1),(−4,6),(−3,−5)

Let us Assume A(x

1

,y

1

)=(1,−1), B(x

2

,y

2

)=(−4,6) and C(x

3

,y

3

)=(−3,−5)

We know that,

Area of triangle =

2

1

[x

1

(y

2

−y

3

)+x

2

(y

3

−y

1

)+x

3

(y

1

−y

2

)]

Therefore,

Area of the given triangle =

2

1

[{1(6−(−5))}+{(−4)(−5−(−1))}+{(−3)((−1)−6)}]

⇒

2

1

{11+16+21}

⇒

2

48

=24 square units

Hence, the area of the triangle with given vertices is 24 square units