The two lines y=x and x=-9 intersect on the coordinate plane. What is the value of the area of the figure formed by the intersecting lines and the x-axis?
Answers:
A) 32.5	B) 36.5	C) 40.5	D) 44.5	E) 48.5
The point of intersection is (-9,-9).   The triangle has a base of length 9 and a height of 9.   area = (1/2)*base*height = (1/2)*9*9= 
<gadget id="calculator">(1/2)*9*9</gadget>
<output>81/2 = around 40.5</output>
40.5   The answer is 40.5.
<result>C</result>
The two lines y=x and x=-9 intersect on the coordinate plane. What is the value of the area of the figure formed by the intersecting lines and the x-axis?