Question

PLEASE PLEASE HELP

Part A::(subtract the polynomials)
(SHOW ALL WORK)!!

(3-6n^5-8n^4) - (-6n^4-3n-8n^5)

(Part B:: solve the quadratic)

SHOW ALL WORK
4x^2-2x-5=0

Thanks

Answer 1

`(3-6n^5-8n^4) - (-6n^4-3n-8n^5)\\\\=3-6n^5-8n^4+6n^4+3n+8n^5\\\\=(8n^5-6n^5)+(6n^4-8n^4)+3n+3\\\\=\boxed{2n^5-2n^4+3n+3}`



`4x^2-2x-5=0\\a=4;\ b=-2;\ c=-5\\\\\Delta=b^2-4ac\\\Delta=(-2)^2-4\cdot4\cdot(-5)=4+80=84\\\sqrt\Delta=√(84)=√(4\cdot21)=2√(21)\\\\x_1=(-b-\sqrt\Delta)/(2a);\ x_2=(-b+\sqrt\Delta)/(2a)\\\\x_1=(-(-2)-2√(21))/(2\cdot4)=(2-2√(21))/(8)=(1-√(21))/(4)\\\\x_2=(-(-2)+2√(21))/(2\cdot4)=(2+2√(21))/(8)=(1+√(21))/(4)`