In the coordinate plane, points (x, 6) and (10, y) are on line k. If line k passes through the origin and has slope 1/2, then x * y = Pick one.
A) 52
B) 46
C) 60
D) 50
E) 35
Line k passes through the origin and has slope 1/2 means that its equation is y=1/2*x.   Thus: (x, 6)=(12, 6) and (10, y) = (10,5) --&gt; x*y=12*5= 
<gadget id="calculator">12*5</gadget>
<output>60</output>
60.   Answer: 60
<result>C</result>
In the coordinate plane, points (x, 6) and (10, y) are on line k. If line k passes through the origin and has slope 1/2, then x * y =