In the coordinate plane, points (x, 8) and (20, y) are on line k. If line k passes through the origin and has slope 1/4, then x * y =
Choose the most appropriate option:
A) 120
B) 100
C) 135
D) 140
E) 160

Rationale: line k passes through the origin and has slope 1 / 4 means that its equation is y = 1 / 4 * x . thus : ( x , 8 ) = ( 32 , 8 ) and ( 20 , y ) = ( 20,5 ) - - > x * y = 32 * 5 = 160 . answer : e
Answer: E