Question

HELP PLEASE!

Answer 1

Answer        

Find out the Area of a triangle .

To proof  

Formula

Area of Triangle

$= \frac{1}{2}\times( {x_1(y_{2}-y_{3}) +x_{2}(y_{3} - y_{1})+x_{3}(y_{1}-y_{2})})$

Now vertices are D(3, 3) , E(3, −1) , and F(−2, −5) .

$= \frac{1}{2} (3\times(-1 +5) + 3\times(-5-3)-2\times(3+1))$

Solving the above

$= \frac{1}{2}(3\times4+3\times-8 -2\times4)$

$=\frac{1}{2} (12-24-8)\\ =\frac{1}{2} (-32+12)\\=\frac{1}{2} (-20)$

= -10 units²

(Neglected the negative sign as area cannot be negative.)

= 10 units ²

Area of  a triangle is 10 units ²

Hence proved