Add or subtract as indicated.
-$\left(7+5 x^{6}+9 x^{8}-2 x^{7}\right)+\left(-9 x^{7}-2 x^{6}-4+4 x^{8}\right)$
A) $-2 x^{8}-2 x^{7}+5 x^{6}+2$
B) $13 x^{8}-11 x^{7}+3 x^{6}+3$
C) $5 x^{42}+3$
D) $13 x^{16}-11 x^{14}+3 x^{12}+3$

Question

Quizplus · Accepted Answer

Combine like terms: $9x^8 + 4x^8 = 13x^8$, $-2x^7 - 9x^7 = -11x^7$, $5x^6 - 2x^6 = 3x^6$, and $7 - 4 = 3$.

Add or Subtract as Indicated (7+5x6+9x8−2x7)+(−9x7−2x6−4+4x8)\left(7+5 x^{6}+9 x^{8}-2 x^{7}\right)+\left(-9 x^{7}-2 x^{6}-4+4 x^{8}\right)(7+5x6+9x8−2x7)+(−9x7−2x6−4+4x8)

Add or Subtract as Indicated $\left(7+5 x^{6}+9 x^{8}-2 x^{7}\right)+\left(-9 x^{7}-2 x^{6}-4+4 x^{8}\right)$