Answer:
it is A
Step-by-step explanation:
you need to distribute the terms [tex]3x^2[/tex] and -4 into their respective parentheses.
[tex]3x^2*x =3x^3[/tex]
[tex]3x^2*3=9x^2[/tex]
so the left side completed is [tex]3x^3+9x^2[/tex]
next do the other side
[tex]-4*1 =-4[/tex]
[tex]-4*-2x^2 =8x^2[/tex] (remember - * - = +)
Right side complete is[tex]-4+8x^2+7[/tex]
both put together is [tex]3x^3+9x^2-4+8x^2+7[/tex]
combine like terms to get
[tex]3x^3+17x^2+3[/tex]
