In a rectangular coordinate system, what is the area of a rectangle whose vertices have the coordinates (-9, 1), (1, 1), (1, -8) and (-9, -8)?
Choose the most appropriate option:
A) 72	B) 180	C) 70	D) 90	E) 140
Length of side 1= 9+1= 
<gadget id="calculator">9+1</gadget>
<output>10</output>
10   Length of side 2= 8+1= 
<gadget id="calculator">8+1</gadget>
<output>9</output>
9   Area of rectangle= 10*9= 
<gadget id="calculator">10*9</gadget>
<output>90</output>
90   90 is the answer
<result>D</result>
In a rectangular coordinate system, what is the area of a rectangle whose vertices have the coordinates (-9, 1), (1, 1), (1, -8) and (-9, -8)?