31. Resolvé las siguientes operaciones. a. \( 5\left(x-x^{2}\right)+4 x^{2} \cdot 2 x-(3 x)^{2}-12 x^{3}= \)

1) \( \frac{10 x+8}{3 a-b}-\frac{9 x+5}{3 a-b}= \)

In the \( x y \)-plane, a parabola has vertex \( (9,-14) \) and intersects the \( x \)-axis at two points. If the equation of the parabola is written in the form \( y=a x^{2}+b x+c \) where \( a, b \), and \( c \) are constants, which of the following could be the value of \( a+b+c \) ? (A) -23 (B) -19 (D) -12

Roger was told to think of a number, add 20 , then divide the result by 3 . The answer was Jower than Roger's original number. Deteruine the range of possible numbers Roger may have originally chosen.

tinh \( a x^{2}+2 x+3 y=6 \)

Subtract the polynomials: \( (5x^{3} + 2x^{2} - 7) - (3x^{3} - x^{2} + 4) \)