First find x and y.
Solve system of equations by elimination.
3x-y=3
+(-x+y=3)
---------------
2x=6
x=3
Now plug in x into one of the equations to find y.
-3+y=3
y=6
xy=3x6=18
The first option is correct (:
3.9 x 10 ^-5 is the answer. 0.000039 in scientific notation is 3.9 x 10^-5
