Answer:
Area of ΔQRS is 140 unit².
Step-by-step explanation:
Given: Coordinates of ΔQRS, Q( -9 , 5 ) , R( 6 , 10 ) & S( 2 , -10 )
To find: Area of triangle ΔQRS
Area of triangle is given by following formula,
[tex]Area=\frac{1}{2}\left |x_1(y_2-y_3)+x_2(y_3-y_1)+x_3(y_1-y_2)\right|[/tex]
[tex]Area\:of\:\Delta\,QRS=\frac{1}{2}\left |-9(10-(-10))+6(-10-5)+2(5-10)\right|[/tex]
[tex]=\frac{1}{2}\left |-9(20)+6(-15)+2(-5)\right|[/tex]
[tex]=\frac{1}{2}\left |-180-90-10\right|[/tex]
[tex]=\frac{1}{2}\left |-280\right|[/tex]
[tex]=\frac{1}{2}\times280[/tex]
= 140 unit²
Therefore, Area of ΔQRS is 140 unit².
