(apex) which expression is equivalent to (x^2-2x) (3x^2+4x-7)

options are:
a.
x^2(3x^2+4x-7)-2x(3x^2+4x-7)
b.
x^2(3x^2+4x-7)+2x(3x^2+4x-7)
c.
x^2(3x^2+4x)-2x(4x-7)
d.
x^2(3x^2+4x-7)-2x

The party planning committee has to determine the number of tables needed for an upcoming event. if a square table can fit 8 people and a round table can fit 6 people, the equation 150 = 8x + 6y represents the number of each type of table needed for 150 people.