[tex]\text{Simplify:}\\\\7x^2(6x + 3x^2- 4)\\\\\text{Use the distributive property:}\\\\42x^3+21x^4-28x^2\\\\\text{You can arrange them by exponent}\\\\21x^4+42x^3-28x^2\\\\\text{This means that your answer will be C).} 21x^4 + 42x^3 - 28x^2\\\\\boxed{\text{C).}\,\,21x^4 + 42x^3 - 28x^2}[/tex]
