Question

Simplify (7x + 2 + 8x4) – (2x – 5 – 8x4) + (3x + 5x4)

A. 15x4 + 14x + 7
B. 21x4 + 8x + 7
C. 21x4 + 14x + 7
D. 15x4 + 19x + 7

Answer 1

`(7x+2+8x^4)-(2x-5-8x^4)+(3x+5x^4)\\\\=7x+2+8x^4-2x+5+8x^4+3x+5x^4\\\\=(8+8+5)x^4+(7-2+3)x+(2+5)\\\\=\boxed{21x^4+8x+7}\to\fbox{B.}`