Question

Solve 7x²+8x+1=0 using quadratic formula

Answer 1

`7x^2+8x+1=0\\\\a=7;\ b=8;\ c=1\\\\\Delta=b^2-4ac;\ if\ \DElta > 0\ then\ x_1=(-b-\sqrt\Delta)/(2a)\ and\ x_2=(-b+\sqrt\Delta)/(2a)\\\\\Delta=8^2-4\cdot7\cdot1=64-28=36;\ \sqrt\Delta=√(36)=6\\\\x_1=(-8-6)/(2\cdot7)=(-14)/(14)=-1;\ x_2=(-8+6)/(2\cdot7)=(-2)/(14)=-(1)/(7)\\\\Answer:x=-1\ \vee\ x=-(1)/(7)`