Help! i’m not tryna fail math this year team work makes the dream work !

If f(x)=2x-6 and g(x)=3x+9, find (f-g)(x)

What is the number 321,000,000 in scientific notation? also what is the number? ?

How is the equation of this circle written in standard form? x2 + y2 - 6x + 14y = 142 a) (x - 3)2 + (y + 7)2 = 200 b) (x+ 3)2 + (y - 7)2 = 200 (x - 6)2 + (y + 14)2 = 142 d) (x+6)2 + (y- 14)2 = 142