In a rectangular coordinate system, what is the area of a rectangle whose vertices have the coordinates (-5, 1), (1, 1), (1, -4) and (-5, -4)?	Select the correct option:  A) 20  B) 30  C) 40  D) 55  E) 48
Length of side 1= 5+1= 
<gadget id="calculator">5+1</gadget>
<output>6</output>
6   Length of side 2= 4+1= 
<gadget id="calculator">4+1</gadget>
<output>5</output>
5   Area of rectangle= 6*5= 
<gadget id="calculator">6*5</gadget>
<output>30</output>
30   30 is the answer
<result>B</result>
In a rectangular coordinate system, what is the area of a rectangle whose vertices have the coordinates (-5, 1), (1, 1), (1, -4) and (-5, -4)?