Question

What is the area of the rectangle?

Answer 1

Take a look at the picture i sent you

Answer 2

Use the formula of length of the segment:
$A(x_A;\ y_A);\ B(x_B;\ y_B)\\\\|AB|=\sqrt{(x_B-x_A)^2+(y_B-y_A)^2}$

$A(-3;-7);\ B(5;-1)\\\\|AB|=\sqrt{(5-(-3))^2+(-1-(-7))^2}=\sqrt{8^2+6^2}=\sqrt{64+36}=\sqrt{100}=10\\\\A(-3;-7);\ D(-6;-3)\\\\|AD|=\sqrt{(-6-(-3))^2+(-3-(-7))^2}=\sqrt{(-3)^2+4^2}=\sqrt{9+16}=\sqrt{25}=5$
$A_{\boxed{ . }}=|AB|\cdot|AD|\\\\A_{\boxed{ . }}=10\cdot5=50\ \text{units}^2$